Pioneer DVR-108 won't read bought DVD movie

I have a DVR-108 that wil burn data discs and read data discs just fine. However when I place a purchased OR burned movie in to the player I will hear audio that plays in spurts, but the video has frozen on the menu or one of the other intro parts of the movie. The machine locks up at this point and needs to be rebooted using the reset button.

The burner was purchased at the same time an ATI Radeon 7000 card was purchased and the installation of both pieces of hardware caused multiple problems. I formatted and reinstalled the system this weekend and my friend seems happy with it (his machine) but the DVD problem persists. Also, using Nero 6 software there should be an options under favorites to “Make Your Own DVD Movie”, “Make a Movie” or “Copy DVD”, but non of those options shows up after the reinstall. When they DID show up before the re-install the same video freeze issue existed where I could hear audio playing, but no video movement, then an eventual lock-up.

Ideas?