I Removed Unity Just fine and Dandy.. I Hate Unity.. cant Stand it.. I Love ubuntu.. But Bah Unity.. Junk..
Here is how I removed it.
If you only want to remove Unity itself and not all of the applications that come with it all you need to do is remove the actual Unity and Unity 2D packages with the command below:
to completely remove the Unity
sudo apt-get remove unity unity-2d
But you will need something in its place so you can either use gnome3 or gnome fallback if you want v2.
sudo apt-get remove unity unity-2d-places unity-2d unity-2d-panel unity-2d-spread unity-asset-pool unity-services unity-lens-files unity-lens-music unity-lens-applications gir1.2-unity-4.0 unity-common indicator-sound indicator-power indicator-appmenu libindicator6 indicator-application evolution-indicator indicator-datetime indicator-messages libnux-1.0-0 nuxtools
And im now a happy camper with no more unity using 12.04. Or if you dont wanna go though all that.. Xubuntu is your friend.
sudo apt-get install gdm gnome-shell