Q:

Revert from Gnome 3 to Unity

Ok, so Ubuntu 14.04 came with Gnome 3 in it's repo and I tried to give it a go, and I didn't like it at all.
So I wanted to continue to use Unity desktop, but it kept freezing and I couldn't change background. Right click also isn't working on desktop. 
Is there a way to delete all of Gnome 3 and reinstall Unity like it would be after fresh install?

A:

Open Terminal or CTRL+ALT+T
To install Unity
sudo apt-get install ubuntu-desktop unity
To Remove Gnome
sudo apt-get remove gnome-shell ubuntu-gnome-desktop
and reboot the system sudo reboot
If followed above 3 commands, you should be greeted with Unity session after reboot. In case it still doesn't comes up, open terminal and execute unity --replace
PS: by chance anything from gnome is left, follow https://askubuntu.com/a/244658/86467

