First off, what do you have for a system? XP, Vista, 7??? I can help with XP.
Hopefully, you have a good anti-virus program (avast is one of the best I've found for malware). If not, try and download it from the internet. It's free. f you can't download it, try and log on to the net in safe mode. Try that. Run a thorough scan. Archive files too. That should do the trick. Avast will prompt you to fix, delete, or quarantine the virus. I'd put it in quarantine for now.
Another fix might be to try and use one of your restore points in Windows. I know that XP uses them. It will bring your pc back to a previous date and removed any files that were loaded after that date. For example, the pc automatically sets the restore points. Lets say your system's restore points were Thursday, Friday, Saturday, and Sunday. You got the malware on Saturday. You can pick a restore point from Friday and any files that were downloaded onto your system AFTER Friday will be wiped.
Before you mess with the restore point, try and load avast. Any other operating system, maybe somebody else can offer advice. XP is all I know.
Good luck,
Obie