Full DVD support on Linux is an old issue. It has to do with the Linux distros not being shipped with the w32codecs and the libdvdcss2, for legal reasons in some countries. The users must then download and install them by themselves with no clear guidance.
Here are the simple steps for installing these libraries under Debian based distributions.
The GUI Route: (CLI users forgive me but if there’s a GUI, users diserve a choice.)
1 – Download the w32codecs
2 – Download the libdvdcss2
3 – Double click on the packages, one at a time and use the Package Installer to install them quickly and painless
The CLI (Command Line Interface) route
wget -c http://www.debian-multimedia.org/pool/main/w/w32codecs/w32codecs_20071007-0.1_i386.deb
sudo dpkg -i w32codecs_20071007-0.1_i386.deb
wget -c http://www.debian-multimedia.org/pool/main/libd/libdvdcss/libdvdcss2_1.2.9-0.0_i386.deb
sudo dpkg -i libdvdcss2_1.2.9-0.0_i386.deb
See this relared post about OpenSuse and SLED10