Welcome to the forum!
Bit of a coincidence that the drive would stop reading CDs after an OS reinstall.
Is there any other software installed that would interfere with drive operation - maybe burning programs like Nero (specifically the InCD portion), Roxio (inc. Drag 2 Disc) etc, or virtual drive/emulation software like Alcohol, MagicISO, or Daemon Tools etc?
Geno's boot disc suggestion is a good one, it would rule in or out any software/OS problems.