Make Your PC Run Faster and Better

First Do Essential Housekeeping
Before undertaking any system changes, be sure that the basic maintenance chores are done. Also be sure that you know how to get back where you started in case changes don't work out. As a reminder here are the things that need to be done regularly: 
Run up-to-date anti-virus
Run up-to-date anti-spyware (preferably two or more)
Empty “temp” files
Empty Recycle Bin
Run chkdsk and disk defragmenter
Back up your system 
Make your computer start faster
Getting the computer up and running involves several stages. There are various tweaks that can be applied for each stage to speed things up. In my own experience, only a few make much difference. Some references are given in the sidebar. The most important improvement by far comes from controlling the programs that are loaded at start up. This item will be discussed in more detail below but first here is a survey of other possibilities. 
The boot process involving the BIOS 
There are a variety of tweaks that are possible in this first stage but I have never found one that did more than shave a second or two here and there. Furthermore, the BIOS is terra incognita for the average PC user. There are probably more fruitful areas where time-saving measures can be looked for but those who love to tinker can get some ideas from this ExtremeTech reference.
About Bootvis.exe
This graphical Microsoft developer tool is mentioned and recommended as a way to speed up booting in countless places. I see it so often that I felt constrained to devote a separate section to it. This is what Microsoft has to say
Please note that Bootvis.exe is not a tool that will improve boot/resume performance for end users. Contrary to some published reports, Bootvis.exe cannot reduce or alter a system's boot or resume performance. The boot optimization routines invoked by Bootvis.exe are built into Windows XP. These routines run automatically at pre-determined times as part of the normal operation of the operating system.
From what I understand (I'm no expert) a brand-new setup might take a couple of days before Windows XP finishes optimizing and, if you just can't wait, Bootvis.exe might help you optimize right away . But, basically, you can forget about using this tool in spite of what everybody keeps saying. You can't even download it from Microsoft anymore although there are sites that still have it. There seem to be several versions and one or more may not work in SP2. 

In any event, it seems it is possible to carry out some of the type of optimization done by this tool just by using RUNDLL32.EXE. In Start-Run. Enter the command 
RUNDLL32.EXE advapi32.dll,ProcessIdleTasks
Loading Windows
Windows XP loads pretty fast but there are some ways to hurry it up a bit. Unfortunately, a lot of the stuff you read isn't too useful. Here are a few of the common suggestions. 
A study has shown that cutting down on the number of fonts being loaded will speed things up. If you have many hundreds of fonts, you might consider removing some. Those who wish to manage their fonts can read this article. 
There is a lot of discussion of configuring "Prefetch" and the related subject "boot defrag". The average PC user can ignore these subjects since Windows XP basically takes care of this area on its own. These configurations are part of what the utility "Bootvis.exe" discussed above was supposed to help manage. If you must tinker, do the RUNDLL32.exe command given above in the Bootvis.exe section. However, forget the often-mentioned idea of regularly deleting the contents of the \Windows\Prefetch\ folder. In fact, deleting Prefetch will initially slow down the boot until the folder is rebuilt. See Ed Bott's blog on the subject. Also see this bad tweaks list. 
The Start menu in Windows XP contains an entry, My Recent Documents, where a list of all the recent documents that you have opened or used is kept. This provides a quick way to reopen any document. After a while the list can get quite long and it has the effect of slowing the bootup process. Details of managing this feature are discussed here. What isn't obvious is that the list of files that can be accessed from the My Recent Documents entry in the Start may be only the tip of the iceberg. The folder, %USERPROFILE%\Recent, where the entries are stored may have many more. This folder should be cleaned regularly. This can be done manually or automatically every time you log off. To make the cleanup automatic you can edit the Registry. (The usual caveats about Registry editing apply.) In the Registry editor Regedit, navigate to this key: 
HKEY_CURRENT_USER\Software\Microsoft\Windows\ CurrentVersion\Policies\Explorer
Create a DWORD value named ClearRecentDocsOnExit and give it a data value of 1. Shortcut entries for “My Recent Documents” will still be collected during a login session but will then be cleared at logoff.

For those who shun Registry editing, I have written an INF file to do the Registry change. Download the zipped file here to anywhere convenient and unzip. Then right-click and choose “Install” from the context menu. The change will take place when you log off or reboot.
Note: This file is offered without any guarantees and the user assumes all respnsibility for its use.
Drivers and hardware
Part of the boot process is loading and initializing the hardware. 
Keep the drivers for your peripherals and other hardware up-to-date. This may require checking regularly at the Web sites of the manufacturers. If you have older equipment, be sure that you are using drivers written for Windows XP. 
You may want to disable rarely used peripherals or hardware services. Possible examples are game ports, IR ports, MIDI devices, and Firewire. Disabling devices does not remove them and they can be re-enabled if desired. Use Device Manager to make changes. Click here to see how to use Device Manager. 
Networking tweaks
Network cards can be a substantial drag on startup time since they can spend a lot of time getting network addresses. Also if you have a lot of network protocols , loading them can take time. 
If you have a home network and are using automatic IP assignments, you may be able to speed things up by assigning permanent IPs to the computers on your network. Consult the instructions for your router. Also see this reference.
If you are using DSL and connect by PPPOE directly to a modem (not a router) you definitely want to assign a permanent IP to your network card. Otherwise, there is a considerable delay while the card hunts for an address when you boot. Consult your ISP for instructions. Also see this reference.
Limiting the programs and services that start up

This area is where the big savings in time can be made. The average PC user probably has far too much stuff loading at start up. Also, Windows starts up a lot of services by default that many systems do not need. The measures to take are covered in great detail on pages elsewhere on this site. How to use the Windows System Configuration Utility (Msconfig) and the Services Console to control both programs and services is discussed. There is also some excellent freeware to help manage your startup and one program, WinPatrol, is evaluated here. 
Making the system run better

Controlling what starts up is also a major way to make your system faster and more efficient once it is up and running. Other ways to help your system run more efficiently are discussed on the
Control What Runs in the Background
Caveat
An absolutely essential prerequisite is the absence of malware and adware. Unless a machine is free of these pests, there is no point in discussing other performance topics. Also, make no system changes unless you know how to undo them 
What background processes are 
The computer is always carrying out processes that are not visible as programs on the Desktop or the Taskbar. They come both from application software and from Windows. They are not overtly obvious and are said to run in the background. Many of them are essential functions but some may be useless (or even harmful if malware is involved).
The problem
The typical home PC today is likely to be stuffed with background programs and services. Windows XP is quite good at handling a lot of simultaneous processes but too many can consume enough resources to noticeably affect system performance. Also, some programs are poorly written or consume so many resources (Norton SystemWorks comes to mind) that by themselves they create a problem.
Where unnecessary background processes come from
There are several sources. 
It is all too common for software companies to pile on a lot of unnecessary features that load into the background at startup. 
Even Windows XP has a default configuration that loads a lot of services that typical home users do not need or use. 
In today's climate a substantial amount of protection against malware and crackers is required. This involves several programs running in the background. These programs are often resource-intensive and require careful configuration. They may conflict with one another if default settings are used. For example, it is easy to end up with three different programs checking your email attachments. Personally, I prevent a lot of functions from running automatically and instead use a regularly scheduled manual routine. 
Solutions
As mentioned on the previous page, the measures to take are covered in great detail on pages elsewhere on this site. How to use the Windows System Configuration Utility (Msconfig) and the Services Console to control both programs and services is discussed. There is also some excellent freeware to help manage what runs in the background and one program, WinPatrol, is evaluated here. Below is a table showing examples of some services that might be unnecessary. Others are given in the references above. 
Some Candidates for Unnecessary Services Computer Browser Keeps track of the other computers on your network 
Error Reporting Service Reports failures of applications directly to Microsoft 
Fast User Switching To switch to other users on the same system without logging off 
Indexing Service Creates a searchable database of hard drive 
Messenger To send text popup messages to computers on the network
Remote Registry For remote connection to the Registry
Terminal Services Allows users to connect to the computer with remote desktop
Wireless Zero Configuration Configures wireless 802.11 devices

Configure Windows XP

Some basic tweaks that help performance are discussed on another page in a previous article. Many tweaks are given in the references listed there and in the previous page. Some examples are:
Disable Error Reporting to Microsoft 
Configure System Restore to take up less space
Change Visual Settings to remove "eye candy"
Turn off fancy animated visual effects
Use Windows more efficiently