Due to legal reasons, Ubuntu cannot provide the additional software on the Ubuntu cd needed to play DVDs. Run these to commands in the terminal to install the software.
Be sure to read about restricted formats here before running the commands below. There are some legal issues that you should be aware of.
Open the Terminal under Applications > Accessories > Terminal and run the following command.
sudo apt-get install libdvdnav4 libdvdread4 gstreamer0.10-plugins-bad gstreamer0.10-plugins-ugly
Alot of newer DVDs are encrypted. You will need to run this command to be able to play those DVDs.
You will now be able to insert a DVD and open it with Movie Player (Totem). I suggest you install VLC Media Player from the Ubuntu Software Center and use that program to play your DVD.
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