So obviously, when I said "restoring my FreeBSD partition to bootable status" what I meant was "accidently render Windows XP unbootable and while attempting to fix that accidentally install Windows over my FreeBSD partition, losing years of accumulated stuff that was sitting, not backed up, in my home directory."
Oops.
Anyway, now I've got a freshly installed FreeBSD partition and a freshly installed Windows XP partition, and everything is playing nice with everything else, which is nice. I decided to play with subversion today, rather than going right back to NWN, and fixed a little bug, so at least the day wasn't a total waste.