You can install Ubuntu by downloading it, buning it on a cd/DVD or a USB.

install Ubuntu, When booted in Ubuntu follow the steps bellow.

step 1

Remove the Video Lens that comes with the YouTube scope or else there will be conflicts:

sudo apt-get remove lens-video

Install Ubuntu TV using the test PPA

sudo add-apt-repository ppa:nilarimogard/test3

sudo apt-get update

sudo apt-get dist-upgrade

sudo apt-get install unity-lens-video

step 2

To generate previews for your videos (which should be placed under ~/Videos/unity/local/featured ), use:
edit the ~/Videos to wherever you have your Videos

/usr/lib/unity-lens-video/create_tmb.sh ~/Videos

step 3

Logging in to Unity 2D won't work and you must run Ubuntu TV from the session you're currently logged in so open a terminal and copy/paste the following commands:

gsettings set com.canonical.Unity2d form-factor tv

if you were running Unity 2D already:

killall unity-2d-{panel,places,launcher,spread} && killall unity-2d-{panel,places,launcher,spread}

for unity 3d / Gnome-shell

metacity --replace &

to run ubuntu-tv copy/paste this in gnome-terminal

unity-2d-shell -opengl

to Close ubuntu-tv run this

for unity

unity --replace

for gnome-shell

gnome-shell --replace   

To revert the changes

sudo apt-get install ppa-purge

sudo ppa-purge ppa:nilarimogard/test3

sudo apt-get remove unity-lens-video

Source:

How To Install Ubuntu TV From A PPA ~ Web Upd8: Ubuntu / Linux blog

If you want to compile it from source(ubuntu-tv)

use this

sudo apt-get build-dep unity-2d

sudo apt-get install bzr dconf-tools ffmpeg gnome-common libdeclarative-multimedia

bzr branch lp:~s-team/ubuntutv/trunk ubuntu-tv

cd ubuntu-tv

cmake .

make

cd ..



bzr branch lp:~s-team/ubuntutv/unity-lens-video

cd unity-lens-video

./autogen.sh --prefix=/usr --sysconfdir=/etc

sudo make install

cd ..

There are four dirs to be filled with media:

- ~/Videos/unity/local/featured



- ~/Videos/unity/local/rented



- ~/Videos/unity/local/purchased



- ~/Videos/unity/local/recorded

Generate thumbnails for your videos:

/usr/lib/unity-lens-video/create_tmb.sh "~/Video's/"

To refresh the video list

cd

cd ubuntu-tv/shell/dash/epgdata

python refreshdata.py

cd 

Set the formFactor D-Conf key to “tv”

GSETTINGS_SCHEMA_DIR=ubuntu-tv/data gsettings set com.canonical.Unity2d form-factor tv

Prepare your environment
if you’re running unity-2d, you need to kill unity-2d-panel, unity-2d-places, unity-2d-launcher, unity-2d-spread (twice):

killall unity-2d-{panel,places,launcher,spread} && killall unity-2d-{panel,places,launcher,spread}

Run it like so:

metacity --replace &

cd ubuntu-tv

./shell/app/unity-2d-shell -opengl