|If you can do a system restore to a time before it was installed, it will not delete it, but will effectively inactivate it by returning the registry and system files to how they were before the infection was installed. This will give you a window of time in which you can use products like Malwarebytes and your antivirus program to clean it out completely from your system. If you can not get into Safe Mode (F8 at start up and select Safe Mode), see if you can start the System Restore from there. If you cannot do that, you can use Windows 7 Repair Disk, put that into your CD/DVD drive and boot to that (you may need to 'hit any key to boot from CD/DVD' or you may actually need to reset your boot order in your BIOS first to boot from your optical drive), then under the repair options, you will see an option to perform a System Restore using restore points on your hard drive, but the undamaged restore program on the repair disk. You should have made a Repair Disk when the computer was new, but if you did not, you can still make one from any Windows 7 machine that is running well, and is of the same type (32bit or 64bit) and use that.|
Once you successfully perform the restore, reboot into Safe Mode with Networking and download, install, update, and run Malwarebytes, removing anything it finds. Then update and run your antivirus program. If you no longer trust the antivirus program you currently use, uninstall it and install Avast Free version (free if registered) or Webroot Secure Anywhere (free trial only so you would need to pay for it, decent discounts for 3 or 5 machines) and run that instead.
You have to be a little bit crazy to keep you from going insane.