I think you already heard about VLC Media Player ,and also seen the performance on the windows machines . I must tell you that VLC performs very good in Ubuntu also!
How to get VLC running in Ubuntu:
1) Go to Terminal (Applications > Accessories > Terminal)
2) Copy the following command line and press enter:
sudo apt-get install vlc vlc-plugin-esd mozilla-plugin-vlc
or Press this link in order to automatically install the packages.
3) If you are asked a Y/n question answear with yes.
4) That’s all! Run VLC Media Player from Applications > Sound and Video > VLC Media Player
Regards
