There's a virus in my PC! I need help :S

[Mr.Fedo]

Hi all, i have discovered that there's a virus in my PC that makes the task manager and the registry don't work :S and i have noticed that there is a folder in my C drive and it's called "bifrost" (it contains an "msn" file with a strange icon and it's created in the day the virus infected my PC) and every time I delete it, it comes back ,anyway I formatted my PC but after the format that damn virus is still in my PC and the task manager and the registry are still disabled. When I press Alt+Ctrl+Del an error massage appears "Task Manager has been disabled by your administrator." and when I try to open the registry another error massage appears "Registry editing has been disabled by your administrator." and that Bifrost thing is still in my C drive. Please help me