I have compiled a list of the most interesting and useful programs I have found to date. I keep the installers on my computer, so if the links go down, just contact me and I'll send you the old version.

• Taskbar Shuffle  This allows you to rearrange your task bar in windows!
• Start Menu Organizer   This program gives you a very nice interface for organizing your start menu. I didn't think I needed it... but I was wrong.
  
• Sharp Keys is a program that allows you to remap your keyboard's buttons. Who uses that "Info" button on your laptop, or Caps Lock anyways?
• Visual Task Tips is just something that makes XP prettier, like Vista. It previews a window on your task bar when you hover over it.
• Page Defrag One of the most common complaints of windows users (as well as the reason most people format) is that their computer is getting slow. The older it is, the slower it gets. The reason? The page file! Most people's page files are so fragmented that their computers slow to a craaawwwlll. This will fix that. And speed up your boot.
• Media Player Tray I use Windows Media Player sometimes, but I don't want to have to have my taskbar cluttered. So I took the bonus pack and extracted the EXE that allowed me to do this, without having to install all the other junk. I hope you like it!
• Launchy allows you to index any number of folders on your hard drive for quick, stylish, command-line access to it in a spit second.
• Notebook Hardware Control keeps your computer slower and using less power when you're on battery power. Obviously this is only really useful for laptops, and it's a bit glitchy, but it's the only utility of it's kind that I have ever found. Let me know if there is an open source alternative, or one that isn't so buggy!
• Windows XP Powertoys is a selection of interesting utilities for windows. I would only really reccomend TweakUI (hidden windows settings) and ImageResizer (right-click menu image resizing), but some of the other ones could come in handy.
• DVDShrink lets you "back up" your dual-layer DVDs to single-layer blank DVDs via advanced compression. 
• Handbrake is "A GPL'd multi-platform, multithreaded DVD to MPEG-4 ripper/converter." Basically it lets you put your movies on your portable devices.
• Spybot Search and Destroy is an anti-spyware program. It's excellent. A must have for all computer users.
• Avast! Anti Virus is the best anti-virus I know. It's free for the home user, but quite pricey to the coperate crowd. 
• JKDefrag is a defragmenting program for windows. Did you know that the built-in defragmenter is actually purposefully crippled?
• Paint.NET is your basic MSPaint on steroids, plus layers and infinite undo. Get it. You won't regret it.
• UXTheme Patcher is a program that allows you to change your windows theme to something other than the bland blue or gray (Who uses that disgusting olive? Honestly.) You can get themes from customize.org, or do a search on Google.
• NetMeter is an excellent bandwidth monitoring application. It can't tell the difference between local and internet traffic... but oh well.
• Daemon Tools is a disc emulation program. It has optional spyware in version 4, so I use version 3.74.
• PStart is an application designed for thumbdrives. It just keeps them organized.
• LClock is a clock replacement tool. It makes it easier to read, adds the ability to have a real calendar (with alarms!) and is completly customizable.
• Console is just a nifty console window replacement. It takes a bit of setting up, but it's much nicer to use than the standard command.com
• TCP Optimizer is just one of those utilities that people should always use, but they never do. Did you know that windows purposefully limits your computer's connection? This application will allow you to fix your TCP shortcomings, and speed up everything you do over a network.
• 7-Zip is an open source file archiver. It actually has the best compression out of all the archivers on the internet. Not the easiest interface... but it gets the job done fast.
• WinDirStat is a great application recently recommended to me. It allows the user to visualize exactly where all those bytes have disappeared to. Be ruthless in your hard drive cleaning!
• FileMenu Tools allows you to modify your right-click menu. Has something added itself to this menu, and you can't take it off? This will fix it in no time. If you're looking for something a little more advanced, try ShellExView
  

Larger Applications

These applications are on the larger side, and are not something that one might quickly download and use. I feel that they don't really fit with all the smaller applications above.

• Open Office.org is the best office program out there, and it's free. It's extensible like Firefox, opens and saves in almost all the document formats out there, and includes a large range of applications.
• Songbird is a great, open source media player that can surf the web! It pulls media links out of web pages and displays them as a list. It also has a ton of other features, but you should just see it for yourself. If you're not happy with iTunes or WMP, then this is for you.
• Electric Sheep Screensaver ...yeah it's a screensaver. Except it is so much cooler than any other screensaver out there. It downloads a stream of pre-rendered abstract 3D art using bittorrent. These movies can take up a lot of space so be warned.