Have you examined the business side of the DVD? That's the side of the DVD opposite the labelled side.
Any dirt or scratches there? Most PC DVD players/writers are more sensitive that stand-alone players, and among things, it means they'll react to dirt and scratches in a much more unfriendly manner. A dirty DVD will play, sometimes, cleanly on a stand-alone, and cause endless problems in a PC for copying purposes.
Try cleaning it, and try the rip again.