problems with flash drives and display adapter

Hi there, hope someone can help me with this matter.
I bought a flash drive usb 2.0 at the university yesterday. Used it at
their computer centre and everything was ok (they have WinXp). Then I
go home, plug the pen drive in my prehistorical pc, and it tells me he
needs a driver. Good God, I dunno what to do!
I press ok a couple of times, reboot the pc and the pen drive is now
not even recognised anymore when plugged into the usb door, and the
control panel tells me there's a problem with the main display
adapter. I can only view 16 colours at 640*480 now.
I have win 98se but lost the installation cds, probably while moving
flat. What should I do? I believe it is a drivers issue but I'm fairly
lost!
cheers,
tom