Vista Reboots when DVD inserted into DVD drive

Greetings all,

I am dual-booting XP & Vista on same HD. Problem in Vista Home Premium.

Tonight i tried to play a DVD - put it into DVD drive, started spinning,
light on drive flashing then, all of a sudden, the computer just restarts.

Disabled auto reboot and looked throught Event logs - couldn't see fault
other than "unexpected shutdown."

Tried another DVD (professional one) - does the spinning, lights on routine
then boom, blank blue screen - no error codes nothing.

Can anyone help me get to the root of the problem - why this is
happening???!! I have Nero version 7.7.5.1 installed. I tried playing back
a movie on 2nd HD, no problems.

Any help from the gurus (and wannabe gurus) will be greatly appreciated.



TIA,


Ray