I didn't say memory dump was to do with bad memory, its only used for running a debugger on the raw memory state for analysis. The constant reboots leads me to think about a hardware failure, and RAM was the culprit with my experience with the problem. However it could be other things.
As JohnLynn said, try a linux Live CD like Knoppix, and boot into it. You may be able to use that to recover some files.
Also which of the drives contain the data, the SATA one I assume? Just make a copy of the data onto the other drive for redundancy (unless the hard disk is formatted with NTFS, in which case you'll only be guarunteed read access not write.) And then try to remedy the problem.