i have this problem with a couple of dvd's that i had purchased.
they work perfectly fine in stand alone dvd players attached to the television, but when i put the disc into a dvd drive on a pc it will not recognize the disc.
windows think that there is no media in the drive. i think even the hardware doesn't see the disc because normally when there is a disc in the tray, a light would turn on to show there is a disc inside.
once the disc is inserted, the light would blink as the disc spins up and (i guess) tries to detect the media. then it would go blank (non lit).
the drive works (it is a lite-on 411s), i have put in a lot of other discs (retail dvd's/dvd-r/dvd-rw/retail cd/cdr/cdrw) and they work. it is just with 2 dvd's.
has anyone else had such a problem or can point in a direction where i can find out more info on things such as this?