When I restarted my system this morning (see signature), Windows didn't load. POST proceeded normally without error but then the screen went black -- well, not black but slightly lit gray. And there's no HDD activity at all. I've never seen this behavior before. If there were a problem with the HDD or MBR, there would have been an "insert boot media" message, no?

I checked the BIOS and all looks normal. Although the failure mode doesn't suggest a bad video card, I swapped it out anyway. Same result. If just the card had been bad, the HDD would have been active after POST loading Windows.

I happen to have a Linux Mint iso DVD, so I booted into Linux. From File Manager I was able to mount and navigate the primary partition (FAT32, Windows XP) so the drive appears to be fine.

I'm stumped. I need my computer back to do my work, so timely troubleshooting tips would be greatly appreciated!