Are you looking for a program that will clean up temporary files and stuff?

If you want a basic clean you can't beat cleanmgr.exe (Start - Run - "cleanmgr") Other than that, I'm not sure.

Or do you want to clean up spyware programs?

http://www.download.com/3000-2144-10...age&tag=button
http://www.download.com/Spybot-Searc...ubj=dl&tag=but