Windows Help!

Hello people,
I guess i got carried away with my windows exploration, and i failed to note what the original confromations were before toggling and meddling with my Device manager in WIIN98SE, all i’m left with is no cd-rom,(“the system cannot readmy cd-rom”) faulty “other devices notice” “faulty adapter resoultion” now i can’t even change the screen area beyond 16 colors.
Somebody help.