That worked! Here's what I did exactly:
- Swapped out the HD for a small spare I keep around for backups
- Booted from the HD manufacturer's CD and used it to wipe the spare HD
- Booted from the Windows DVD, install ran successfully
- Rebooted into my new Windows install
- Reflashed the BIOS per Dell instructions
- Swapped back to my original HD
After that, I am back up and running as normal. Didn't even have to reinstall any software! That's a big time savings since this is a work computer with lots of specialty software and complex settings.
Incidentally, there is a roaming IT consultant my [very small] company uses when I can't solve something - I asked him about this, and he said it wouldn't work. Glad I tried anyway! You're a rockstar.