There is no default support od DVD in Ubuntu 9.10. You have to install the following for getting the DVD Support.
First You Have to add the medibuntu repositories
Howto add medibuntu repository
Then open a terminal and run the following Command
$ sudo apt-get install libdvdcss2 && sudo /usr/share/doc/libdvdread4/./install-css.sh
Now your system is DVD Ready. Play and Enjoy DVD Movies.
