Hate to say this, but you may not be able to access the information at all. The files could be corrupted from the crash or the hard drive has bad sectors making it impossible for the cpu to read. Before buying a new mobo and cpu I would have the tech try a known working hard drive in your puter. If it fires up and loads windows your whole problem was the hard drive all along.

I just hope it doesnt cost ya lots of money to figure out and fix.