If you cannot get any other start mode other than what is presented, then the MBR has indeed been infected. Try booting directly to the OS install disk recovery console, and command the Fixmbr
process. You might be lucky.
Best is to mount the drive as a slave or secondary in a host case, or via a USB external case to a known-clean system.. and scan it with the host's antivirus program. Connect the drive after the OS has settled in, if external. A complete scan should clear up any unwanted entities. But if the virus has "taken root", then it could infect other system files.. and they too might be deleted. For reference, the Registry files are located in the Windows\System32\Config folder. But editing them outside of the parent OS (the one that created them) is near impossible. Only an experienced programmer should attempt it.
Yes, this "FBI Money Pack" virus is really nasty! Microsoft's Forum
has hints on what to do. But don't expect a full recovery. You may have to rebuild the OS installation.
F@H.. to solve mankind's maladies.. in our lifetimes!