If your really bored, and want to make it foolproof, try the below. Might need some tweaking
Originally Posted by Cleveland Rock
1. Install Ubuntu Server, during the installation, make sure that when it asks you what programs to install, all are unchecked.
3. Run the below, uncomment the lines that deal with the Canonical Partner repository, press control+x to save
3. Run the following
sudo nano /etc/apt/sources.list
4. Assuming this is his account your logged into, run the following
sudo apt-get install xorg openbox firefox flashplugin-installer gdm
mkdir -p ~/.config/openbox/
echo "/usr/bin/firefox" > ~/.config/openbox/autostart
echo "openbox --exit" > ~/.config/openbox/autostart
6. you should be faced with a GDM screen on login, try logging in, and FF should auto-start. When FF is closed, openbox (should) exit.