I love mplayer, but I can't figure out how to get the DVD menus working. I heard you need to type something like this:
mplayer dvdnav://
but I don't know what comes after that.
Assuming your mplayer has dvdnav support it's -
mplayer dvdnav:// -dvd-device /dev/XXX
Where typically now XXX is sr0 or in some cases sr1