Uninstall or remove Gnome 3 from Ubuntu 11.04 and 10.10

Installing Gnome 3 on Ubuntu may result in breaking or removal of Gnome desktop plugins. In my case, it resulted in removal of network applet, desktop theme and it also crashed my Unity.
Installing Gnome 3 not only crashes Unity but also breaks down Ubuntu classic. If you have confronted similar problems you can very well switch back to Gnome 2.
For getting back to Gnome 2 follow the given steps. This will uninstall your Gnome 3 and activate Gnome 2 again.

In the terminal, type the following commands:

$sudo apt-get remove libgtk-3-common
$sudo apt-get install ppa-purge
$sudo ppa-purge ppa:gnome3-team/gnome3
$sudo apt-get install gnome-pane

Now reboot your system and if the Gnome 2 desktop is still missing, then type the following commands:

$sudo apt-get update
$sudo apt-get upgrade
$sudo apt-get install ubuntu-desktop  

And you are done!