Does a computer that old have a DVD drive in it ? It probably has only a cd-rom drive.
I could be wrong but I suspect this is your conundrum.
grim
This is a PowerMac 8600 running OS 9.1 @ 400mHz at our vacation house, so no point in putting in a newer Mac....we use this for a little email, a little low level digital audio/video/graphics at times but mostly for iTunes playback.
The Mac lives in the bedroom and I`d like to play DVDs at times when the rest of the family is sleeping. I have a Que drive connected which holds my iTunes music on a home-burned DVD, but I can`t play DVD movies, either homemade or purchased. I`ve tried installing a couple of different apps but still no movies.
Help!

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic