'unplayable DVD'

This is just a note about an interesting problem.
Our household owns one dvd which would only play on a laptop with a combo 
dvdplayer/cd burner. It's Hitchhiker's Guide to the Galaxy.
When I got a DVD burner, I found that this dvd would play in that drive, but 
not in the standard DVD drive in the same machine.
I assume that the difference is the drive speed. Ogle reports that it can't 
find VIDEO_TS etc.
I have assumed that setting the drive speed lower with hdparm would help, but 
I haven't tried that yet.
It may explain some of the odd errors people get with dvds not playing.
Liz
-- 
Every Solidarity center had piles and piles of paper ... everyone was
eating paper and a policeman was at the door.  Now all you have to do is
bend a disk.
		-- A member of the outlawed Polish trade union, Solidarity, 
		   commenting on the benefits of using computers in support
		   of their movement.