looks a bit hopeless. 'cos even if you get windows xp on it how are you going to get the keyboard going. it's unlikely to not work early but work later..
I might've seen it once but not in your situation.. it was with a big chunky 2*ps2-1usb adaptor long ago when usb keyboards weren't used as much as nowadays and usb keyboards were more unreliable back then.
You could try starting the CD from a Win9X bootable disc that just goes straight to a DOS prompt, see if you have keyboard there. start win xp setup. it may be winnt.exe or setup.exe on the cd.
if no keyboard, you could start the windows xp setup from autoexec.bat. You'd have to write the autoexec.bat of the boot cd on another computer burn it to cd and use it.
you could use an automated win xp installation.. an unattended installation. I haven't done it before but people do.. just for efficiency.
you may even be able to use a win xp image but if it's from a motherboard with a different chipset then there is a HAL issue to deal with. i've never dealt with that.
i'd probably just hit a wall regarding why the keyboards aren't working! and wouldn't bother going to the trouble of getting win xp on there unless you've already got the win xp thing set up ready to be installed automatically! but even there as i say, with keybs not working at that stage.. even if they did suddenly work in windows, i'd want them working at that stage to save from future aggravation.. and besides.. chances of them suddenly working in windows is possible but perhaps not something to have much hope for..
if your motherboard has issues then it has issues.
you could try changing your power supply, in case that's the cause.