Windows 7: What options exists for Win7 diagnostics/repair in Win PE environment

Hi people!

My nephew asked for help today, his gaming rig will no longer complete the boot. Testing this myself, I found that it halts pretty late in the process, this assumption is based on Windows 7 wanting to send an error report to HQ (Microsoft Corp). And any conceivable "boot path" (using adv. startup options) ends up with the two options "send" or "don't send", and a reboot.

A Windows 7 recovery disk, created on my PC, did not help. Being 14, his attention span compares to single cell organisms. He has created no recovery disk, and has no restore points to fall back on (at least not to my knowledge sofar).

Usually I do what most people do in this case: Format C:, and then a complete reinstall.

When explaining to him what this meant, he begged not to do this. He has a game that he loves, but he has lost the installation CD. So a reinstall would make this game unusable. (I checked with his father if this was true, knowing that ethics and moral is sometimes considered optional among teenagers. My brother confirmed that this was not a torrent, but genuine money out of his pocket).

So, I'm kinda stuck. Tried to do a repair install. but hit brick wall when it asked for drivers. Both the system and I found no drivers. I have no clue what drivers the Windows 7 install proc. wants.

A sevenforum tutorial claimed that you can only do repair install from inside Windows 7. If that is true, then the only thing I got to work with (again, to my knowledge) is the DOS prompt provided by Win PE. The cold and pitiless white cursor is blinking at me with X: in front of it!

Can I run some diagnostic tool from this prompt and figure out if it is the registry, or a system file that is corrupt/missing?

Check the hard drive with the manufacturer's diagnostic tools.
Hard Drive Diagnostics Tools and Utilities (Storage) - TACKtech Corp.
Hard Drive Diagnostic Procedure