Virtually Functionless Comp!!! PLZ HLP!

Hello,

I recently ran a program [ComboFix.exe (I'm pretty sure this is the culprit anyway)] that rendered my computer incapable of virtually any task. I can no longer connect to the internet when other computers around me can, All my antivirus software has been turned off and I cannot turn it back on, My lappy is running Vista, but the appearence changed and makes it look like it's running 98. Many programs/files/folders are inaccessable. I cannot uninstall any programs, and everything is just generally screwed up. The only [worthwhile] thing I am able to do is go into Computer and look for possible candidates of viruses, then delete them, or if I can't (which happens most of the time) I have to go to FileASSASSIN on Malwarbytes -> tools and delete the file there or play around with the properties.

I need help! please and thank you!

SkeetyPabs