If you've made a backup of your DVD with e.g. dvdbackup, you can
play the directory like a regular DVD like this:
$mplayerdvd://-dvd-device~/video/dvd-directory-containing-VIDEO_TS
This is how I tell mplayer to play a video on my HDMI connected TV:
$mplayer-aoalsa:device=hw=0.7file.mp4
The correct values is found via the output from aplay -l.