avi won't play

not a yelpl bug this needs re assignment.

Thank you for taking the time to report this issue and helping to make Ubuntu better. Examining the information you have given us, this does not appear to be a bug report so we are closing it and converting it to a question in the support tracker. We appreciate the difficulties you are facing, but it would make more sense to raise problems you are having in the support tracker at https://answers.launchpad.net/ubuntu if you are uncertain if they are bugs. For help on reporting bugs, see https://help.ubuntu.com/community/ReportingBugs.

Play mp3 and dvd under Ubuntu

First please install https://help.ubuntu.com/community/RestrictedFormats

You need to have extra repositories enabled..

Please first enable the multiverse repository:

Open System → Administration → Software sources → [ Tab Ubuntu software ]
enable "Software restrictecd by copyright or legal issue ( multiverse )"
Close and confirm the repository reload.

Type the following command in a terminal (applications → accessories → terminal)

sudo aptitude install vlc

To get better dvd playback first you need to add the medibuntu http://www.medibuntu.org/ repository to your /etc/apt/sources.list file:
here howto add https://help.ubuntu.com/community/Medibuntu here the medibuntu available software list http://packages.medibuntu.org/

Then to install:

sudo apt-get update
sudo apt-get install ubuntu-restricted-extras
sudo aptitude install libdvdread3 libdvdnav4 libdvdcss2
sudo aptitude install non-free-codecs gstreamer0.10-pitfdll w32codecs ubuntu-restricted-extras

give your user password when requested, you don't see nothing when you type it, then press enter.

Hope this helps