Can I bash it against a blunt object?

Grrrrr. For whatever reason, my comp is now not reading disks. It WAS just 2 days ago. I had a Doctor Who disk in (so I could bring up the Doomsday ending and break my heart all over again any time I wanted. Shaddup.) and then I installed the new XP Service Pack 3, and upon re-start the drive went all whiny and weird and it hasn't worked since. I un-installed the service pack to see if that would fix it, and nacht. It won't read DVDs, it won't read CD-ROMS, it won't read data disks. For some reason, it still reads Audio CDs, but that's not much consolation. D*mmit, I think it's a hardware problem.... I don't have the money for this!