Hmm, I re-read your post and it looks like you might have changed this already. The option is in that same startup and recovery area.
Reschke, I've seen this on some XP SP1 systems also. There are a few things that are likely culprits:
1. You have onboard Lan that is enabled (in the bios) but not used. Windows XP SP1 will take a long time to boot if this is the case. (Turn off onboard Lan in the bios.)
2. Onboard firewire (IEEE1394). Same story, but this isn't something you really want to disable (unless you have no need for firewire.)
3. Onboard Highpoint or Promise ATA/RAID controller. If you aren't using it, disable it.
BTW: The A7N8X deluxe has onboard firewire, and Serial ATA raid. If they aren't in use and enabled it takes WinXP a while to boot up. Just as a side note, board revision 2.0 A7N8X deluxes are starting to hit the market. This board revision is supposed to have a new nForce 2 chipset stepping which can supposedly support 400 MHz FSB Athlon XPs when they are released. If you can, be sure to get one of these. (The previous boards were revision 1.06 and 1.04. They may be able to take 400 MHz FSB Athlon XPs when released with a bios update, but that's not yet official.)