Please go into synaptic and that can be found
System>Adim>Synaptic
It will ask for your pass word. It will be or should be the same one you use to
log into the splash screen. Now once you get Synaptic up. Click on the search
button and type in " restricted formats ". Look for the restrict formats and
click on the square and now click on the apply button. It will now start
installing the restricted formats for you.
Restart FF and enjoy.
Gobby
http://monkeyblog.org/ubuntu/installing/
https://help.ubuntu.com/community/RestrictedFormats#head-7dc8d31ff5c7ccda