Format PC sure no problem........BUT..
The thing is the virus/worm exploits unpatched windows xp, specifically any nt kernel windows.
So lets say you format and install windows xp from your cd. Unpatched you go online, the hacker can send the worm to your pc becoz of the exploit or open an email attachment with it. So you'll kena again almost instanly.
Better just get the patch. Run the fix. Reboot. Run the fix again to be sure.