I have a virus that I can't seem to clean up with anything. The following are my symptoms:

-Can't install new antivirus software (Spybot and Malwarebytes)
-Can't access many websites
-The computer as a whole is running considerably slower and programs tend to crash after a short time.
-The website OEM-search.com keeps popping up (spyware/adware, duh)
-Internet Explorer doesn't display pictures, even after fiddling with all the security settings.
-I.E. and firefox refuse to work, and I can't install chrome, it just crashes upon opening the installer.
-I have lots of startup problems and the computer runs best in safe mode, though it doesn't run well (still really slow, program crashes, can't install programs, etc)

I would rather not reformat my computer because it is a pain, but if that is the only option then I will proceed with the reformat next week.