I suppose someone has to ask the question:
Why do you want the SAM file? If you have the administrator password then you can rewrite it.
Chsh's solution will work, as you will have created a dual boot machine...............but you need to be administrator to do that ;)
On the other hand you could go to the motherboard manufacturer's site and find out how to use the jumper settings to reset the BIOS password. Or just tell us the make and model and I am sure that we can talk you through it.
Your worst case scenario is a reformat and reinstall..............you really haven't told us very much.........for example if it were a repossessed machine you could take out the hard drives, reformat them in another machine then re-install them.
I would advise that you check out who owns the machine and IMPORTANTLY who has the software licence..........Microsoft don't sell it, they licence it?
I am sorry to sound like an "old woman", but I am mortally afraid of giving people advice that gets them into trouble.
I am assuming, of course, that you have the authority and unrestricted physical access to this machine.
Cheers
