I think the easiest thing you could do is to try to enter your computer through safe mode. Chances are if you try to enter your computer in safe-mode the virus won't be able to do anything because in safe mode your computer only run's essential system files and not non essential programs and files on startup. Back-up any of the important files that you would like to keep if you can get on in safe-mode, and back them up to a external hard drive or some sort of online storage. After you have backed up everything the safest thing you could do is System Restore your computer back months or years, or even the latest time possible. Once the computer has been reverted download a new fire wall, antivirus program, and Malwarebytes. Run the full scans incase the virus still managed to stay.
Alternatively instead of system restoring you could re-install your entire OS after backing up your files.