installing full ubuntu system after choosing "custom"

[azz]

You could make them linger in the halls of exploration and have them
install different window managers first:

sudo apt-get install x-window-system-core gdm xterm icewm

or

sudo apt-get install x-window-system-core gdm xterm fluxbox

or

sudo apt-get install x-window-system-core gdm xterm xfce4


-- 
azz