Seems to find a lot of bad stuff on my computer
Key word: "seems." That software is a
rip-off primarily intended to part you from your money. Whatever you do, don't give them a cent (not to mention your credit-card details!). And don't go downloading & running that trash, or other stuff that you don't really know where it comes from. :thumbsdow
CCleaner is a good & trustworthy program that'll clear your "tracks," if that's what you want. If you need a free antivirus for home use, my top recommendation is
AntiVir PE Classic by a long shot. Secunia's
Personal Software Inspector is another great free security tool (checks for known-vulnerable software and shows you how to fix the vulnerabilities).
Further security tips for Windows users:
http://www.mechbgon.com/build/security2.html