iBook G4 rejects discs

My feeling is this might just possibly be a software problem, as a few months ago I deleted certain Apps I wasn't using to save HD space. I haven't used this laptop to play CDs or DVDs for awhile, but I never had this issue before, and the DVD player is there. It's just that any disc I insert is rejected now, even blanks. I read a post that suggested repairing disk permissions worked on an iMac, but it doesn't work here.

Any help appreciated. I would think there'd be some warning indications if the drive was going out. Again, it worked perfectly before.

I don't think I have a hardware test disc around. Would my OS X disc help in any way? Is there a way of testing the software - or would reinstalling the player help? If so, how could I selectively just install the player?

Thanks