Yeah, don't nuke that file.....

user32.dll is a file necessary for running Windows. If you delete the file, Windows won't run. It looks like Troj/User32Hk-A is a modified, infected version of user32.dll created by the virus W32/MarioF-A, which it uses to infect other files and install other viruses/malware.

As for removing it, I'm having trouble finding information on that. Have you tried running Windows in safe mode, and running your antivirus software that way?

I can't say that I have. I am unfamiliar with using safemode at all to be honest. I'm going to collect as much advice as possible for right now and then have my boyfriend help me out when he comes home monday! this info should be very useful though, so thank you!!

http://support.microsoft.com/kb/142676

Right, but the W32/MarioF viruses work by modifying an otherwise valid user32.dll. Windows doesn't work at all without user32.dll, so the virus doesn't replace it with a "fake" one, and it still does normal user32.dll functions in addition to the virus payload.

While I'm not entirely familiar with how Windows versioning works, I think it likely that the virus's infected version of user32.dll would retain normal version information so that people couldn't find out that easily.