So load OS from another harddrive, and try to access the 'suspect' drive from a real OS.
You should try and get the data off that disk asap, a raw copy for example. But you may need some help to do this properly.
You should begin by reading the SMART info from that drive, and seeing if it has a filesystem, partition table and whether you can access some of the data. This would be very risky in a write-casual environment like Windows. To do this truly well, you would need to run a read-only environment such as in Linux.