Another option, replace the optical drive with a new one.
I have an old dell dimension 2400 that i'm trying to get up and running. I installed win xp with service pack 3 on it, and everything seems to work fine, except when i try to play a dvd or cd. (BTW it has 1 gig of memory) I don't think it is hardware related. When i try to play a dvd the sound is almost inaudible and along with the video it starts and stops. The sound sometimes is almost ok but sounds like theres an echo. The cd player is the same way, it plays the cd but starts and stops. I can take both players out and install in another computer and they work just fine. I worked on this for 3 or 4 days off and on and am about to get tired of messing with it. I have run dell diagnostics and installed and reinstalled drivers and checked everything i know of but nothing seems to help.Anyone can help with this i'd sure appreciate it.....thanks