CD-Rom, DVDs not recognized

Recently my dad's dvd rom stopped working, but it still works with computer discs. We tried 2 different DVDs (one we have watched before, one we were trying to watch, and the mouse turned into a disc, but there was nothing in the dvd drive when we looked at the files. We tried a normal cd and an hourglass popped up and the disc worked.

PMs

Any recent updates to WMP, if you updated to the most recent, codecs could have mysteriously "gone missing"