In Ubuntu 10.04 "Lucid Lynx", the universe, multiverse and restricted repositories are activated by default.For installing Multimedia files you need to add medibuntu repositories.
Run the following in command mode it will add medibuntu repositories in your sources list
$ sudo wget --output-document=/etc/apt/sources.list.d/medibuntu.list
http://www.medibuntu.org/sources.list.d/$(lsb_release -cs).list
$ sudo apt-get --quiet update
$ sudo apt-get --yes --quiet --allow-unauthenticated install medibuntu-keyring
$ sudo apt-get --quiet update
Now you can Install non-free-codecs
$ sudo apt-get install non-free-codecsIt will enables your system to support for MP3 and various other audio formats, unrar. Java runtime environment, Flash plugin, Microsoft fonts, w32codecs etc!
You can install more codecs and DVD Support by using
$ sudo apt-get install libdvdcss2 libxine1-ffmpeg gxine mencoderIt will help you to run DVDs, AVI files and other mpeg codecs.
Now Install Famous VLC player and Mplayer
$ sudo apt-get install vlc mplayer
Audio Editing Software Audacity
$ sudo apt-get install audacity
Adobe Acrobat Reader
$sudo apt-get install acroread acroread-plugins
Comments
tstuser@TestVm1004:~$ sudo apt-get install acroread acroread-plugins
Reading package lists... Done
Building dependency tree
Reading state information... Done
E: Couldn't find package acroread-plugins
tstuser@TestVm1004:~$ aptitude search acroread
p acroread - Adobe Reader
v acroread-deu -
p acroread-fonts - Fonts for Acrobat reader - Medibuntu package
tstuser@TestVm1004:~$
Not sure where that package went.