Hi,
Make sure you have SP3 for XP.
I use Avast (is free), F-Prot and Norton Antivirus.
Use Avast to do a full scan. Get windows malicious software removal tool and run it manually to do a full system scan, with Avast or F-prot running in the background.
That should do the trick
Alternatively, remove you hard disk, plug it into a clean computer and scan your disk from the other clean disk.
Works for me,
Toppie.