There prol'ly is a switch in your BIOS to make it look like your USB keyboard is on a PS/2 port. There is in mine, at least.
I picked up Norton SystemWorks 2k1 just for Scandisk, and was I ever pissed when I found out it couldn't fix errors on my main NTFS partition. My temper only became worse when I found out I had to reboot the machine and that it relied on freakin' chkdsk to fix things. For this, I paid $50?
Anyway, I don't know how you'd do it. And I, for one, would not try.