My ASUS A7N8X motherboard had been slowly dying and I was all set to spend some cash and build an up-to-date machine, but then I remembered that I had an old A-Open AK77-8XN board in mothballs, so I threw that in and did a fresh XP install and I'll be darned if the A-Open board didn't work even better than the ASUS board did. I love it when that happens. Now I'm doing a few updates like the SATA stuff and a new graphics card, and I should be good to go for another ten years, lol.
So anyway thanks for the suggestions, especially about the boot up process with an add-in card. I'll have to do some sleuthing in my A-Open's BIOS to make sure that it's capable of booting off a SATA card.