Setting up Ubuntu common stuff

Repositories:

First of all, a basic know how about the application manager. Ubuntu is Debian based and has an excellent integration of "apt-get" or "aptitude" which is the default application manager.
Now we will add software repositories for aptitude to download and install various applications as per our need, for which visit http://www.ubuntu-nl.org/source-o-matic where you select the version of Ubuntu you are using and the architecture. This will generate the list of all the valid available repositories from where we can download the applications that we require. Copy all the lines that are generated and follow these steps:

uniks@uranium:~$ sudo mv /etc/apt/sources.list /etc/apt/sources.list.ORIG
uniks@uranium:~$ sudo gedit /etc/apt/sources.list

This should backup the current sources.list and open a copy of the same for editing in GEDIT editor. Paste all the lines generated by SOURCE-O-MATIC in this file and

uniks@uranium:~$ sudo apt-get update
uniks@uranium:~$ sudo apt-get upgrade

Optionally, if you are using Ubuntu 7.04 (Fiest) you can add these to sources.list:

deb http://us.archive.ubuntu.com/ubuntu fiesty main restricted
deb-src http://us.archive.ubuntu.com/ubuntu fiesty main restricted

## MAJOR BUG FIX UPDATES produced after the final release
deb http://us.archive.ubuntu.com/ubuntu fiesty-updates main restricted
deb-src http://us.archive.ubuntu.com/ubuntu fiesty-updates main restricted

## UBUNTU SECURITY UPDATES
deb http://security.ubuntu.com/ubuntu fiesty-security main restricted
deb-src http://security.ubuntu.com/ubuntu fiesty-security main restricted

deb http://security.ubuntu.com/ubuntu fiesty-security universe
deb-src http://security.ubuntu.com/ubuntu fiesty-security universe

## UNIVERSE AND MULTIVERSE REPOSITORY (Unsupported by Ubuntu.  Use at own risk.)
deb http://archive.ubuntu.com/ubuntu fiesty universe multiverse
deb-src http://archive.ubuntu.com/ubuntu fiesty universe multiverse

## PLF REPOSITORY (Unsupported.  May contain illegal packages.  Use at own risk.)
deb http://packages.freecontrib.org/ubuntu/plf fiesty free non-free
deb-src http://packages.freecontrib.org/ubuntu/plf fiesty free non-free 

Now we are all set to get things running. You can install packages using
sudo apt-get install like

uniks@uranium:~$ sudo apt-get install gftp
where, gftp is the package name.

Installing Multimedia Codecs

Issue the following commands:

uniks@uranium:~$ sudo apt-get install gstreamer0.10-plugins gstreamer0.10-lame gstreamer0.10-ffmpeg gstreamer0.10-lame lame sox ffmpeg mjpegtools vorbis-tools w32codecs gst-register-0.10 libmad0

DVD Playback:

uniks@uranium:~$ sudo apt-get install libdvdcss2