So it went from one computer to the other?
First thing to do is if the computers are connected in a network kill this network, otherwise you won't get rid of the virus.
And then don't use any floppy disks or burnt CD's/DVD's anymore.
Boot viruses are the most harmful viruses and very hard to kill completely. Best way is to ask someone who really knows how to deal with those viruses and knows alot of computers. He might help you with some anti virus software and ways to kill the virus completely.
Very important is that the computer is not connected to any other computer, no floppy disk and no USB stick or such. So isolate the computer.
To buy a Mac doesn't really help here since there are certainly some important data on the hard drives to secure. Also a laptop is way handier than a Mac.
And a Mac costs a lot of money, so there are cheaper ways to get rid of the virus and keep the computer virus free.
Macs are more or less anti virus because most people have PC's with Windows installed. So the people who write viruses rather write a virus for a Windows computer than a Mac, because that affects more people.
But if you don't do anything to secure your Mac it's nearly at the same risk.
