I use VLC personally.
What happens when you load disc?

When I load the disc movie player comes up but it will not play. The program
pretty much locks up. It has to quit before I can eject the disc.

go to help and it will walk you through it.

One is to install the restricted CODECS.
https://help.ubuntu.com/community/RestrictedFormats
One should not do that, but Oh well.

sudo aptitude install vlc gxine mplayer..........