This is almost certainly overkill for an unbootable PC. See Diagnose and Repair an Unbootable XP or Vista PC and Six Downloadable Boot Discs That Could Save Your PC for better advise when Windows won't come up. And speaking of mistakes, never ever run your PC's recovery tool without first backing up your data. In fact, you should never go to sleep without first backing up your data. In this day of cheap external hard drives and automated online backup services, there's just no excuse. Okay, enough lectures. You've made your mistake. Can you get your data back?
Virtually all commercially-sold PCs come with some sort of recovery tool--an alternate way to boot your system (either a CD, a DVD, or a special key combination to press shortly after turning on your PC) that can return your hard drive to its factory condition. Thus, with just a few keystrokes, you can once again have a working copy of Windows, along with all the bundled junk you studiously removed, and none of your own files.
USB Firewall
What's the most popular application software in the world? Most likely, Microsoft Office. You use it, your colleagues use it, your relatives use it, and just about everyone you know uses it. 
This post is more of a note to me so I know what to do whenI need to install XP again, as I have just un-installed Vista after a months use and gone back to XP.
Do you want to make the very best use of your computer's RAM? There are a lot of websites offering performance tweaks and you could spend the next months or more researching the ones you might like to perform, or you can save yourself a lot of bother and read this article. There are hundreds of Windows XP tweaks, but you only need the handful listed here to obtain a significant performance boost. The rest of the tweaks you might find will only give you minor and often indiscernible performance benefits.
