This KB article seems to think you may have found a virus; if the article doesn't help you may have to go the route outlined in the info box below after you have made back-ups of anything you don't want to lose, though the back-ups could be infected also and you'll just import the virus back into the new install.
Be sure to post back with any further questions you may have and to keep us informed.
Information
After you have made backups of everything you care to save and you want to do a real wipe "secure erase" to the Hard Disk Drive (HDD) have a look at this tutorial at the link below, it over-writes everything, all the old Windows code including the old Windows drivers, everything all data, giving you the best possible space to install Windows 7 to; it goes hand-in-hand with a clean install.