I have this old 800mhz box with cdrom. I put in a cd and played a divx file from it easily and copied from the cd easily to HD. Well I just got this new COmpusa dvd dual layer writer and it freezes up everything when I try to play from the cd, I tried copying too and it froze, but it does let you see the contents of the cd as I can browse the cd but whenever trying to mess with anything on the cd it freezes, same for dvds. Anyways is this normal? Im guessin gits the writers, im surprised...if its not compat with linux that surprises me a bit with knoppmyth as I never had a problem with hardware

I can't make out whether you added a DVD-R to your system or replaced your CD-ROM drive. If you replaced the CD-ROM, did you jumper the DVD-R the same as the CD-ROM? It sounds like you may have it set to CS (cable select) instead of Master/Slave...