Intalll the programs below and then what i would suggest is for you to boot into safe mode... if u have xp keep pressing f8 and go into safe mode... then run spybot and windows defender
http://www.download.com/Spybot-Searc...-10122137.html
http://www.microsoft.com/athome/secu...e/default.mspx
If you do not have a "valid" copy of xp there are versions around that dont contain the cd check but i cant help you with that as its against the rules :P...