I like to keep things brief and to the point. Here is how to configure Ubuntu to play DVDs. Tried the procedures on Ubuntu 9.10 up to 11.04, once installed, you will be able to use any proprietary or open-source media player.
Using the Terminal
Install the libdvdread4 package (no need to add third party repositories) via command line:
# sudo apt-get install libdvdread4
libdvdread4 is the decryption mechanism that decodes DVD content. This must be installed or you will not be able to play DVDs.
Then run this program only once:
# sudo /usr/share/doc/libdvdread4/install-css.sh
libdvdread4 and libdvdread4/install-css.sh must be installed first before you install your desired media player. Once the above packages has been installed then you are free to install any media player, for instance, vlc and banshee.
# sudo apt-get install vlc
Installing with the Synaptic Package Manager
To open Synaptic, go to System>Administration> and click on Synaptic Package Manager. Or you can use the shell and type:
# sudo synaptic
Within the synaptic package manager box, click on the "search" button and type: "ubuntu-restricted-extras". A list of possible packages will be displayed. Right-click "ubuntu-restricted-extras" and choose "Install". Search for VLC by typing "vlc" in the "search" bar. Once found, right-click and choose install.
After the initial install, go to the terminal to download and install /usr/lib/libdvdcss.so with this command: "sudo /usr/share/doc/libdvdread4/install-css.sh". After all is complete, enjoy the entertainment.