Thanks for the suggestion, but I'm afraid I'm facing a bigger problem now.
I followed the steps VERY carefully and double-checked each one of them to make sure I didn't miss anything.
Upon entering the command line and hitting enter, the PC rebooted by itself and I'm now stuck with a BSOD.
No idea what the error is, as it reboots within milliseconds of the bluescreen appearing. I barely have time to identify the blue flash as a BSOD before it goes black again.
Startup repair and booting in Safe mode don't work. I can't attach my C drive to another computer because it's a RevoDrive as opposed to a S-ATA device, so I can't retrieve my latest stuff. Luckily I made a backup recently.
I'm afraid I'm giving up on this for now. This has been getting on my nerves for a month now, so I'm going to install Vista and run a full set of hardware diagnostics before I make the switch to 7 again.
I've used the same DVD on my laptop recently (abeit with the serial that came with that one), so I know it's not a file corruption on the DVD. Must be some conflict between win7 and my PC's hardware.