By default, Ubuntu 11.10 uses the Unity desktop. If you don’t like Unity, you can go back to the Classic Gnome Desktop from previous versions of Ubuntu, but it’s not included by default and has to be installed.
To install the Classic Gnome Desktop, press Ctrl + Alt + T to open a Terminal window. Type the following command at the prompt and press Enter.
sudo apt-get install gnome-session-fallback
Enter your password when prompted.
The installation starts with an analysis of what packages need to be installed. The new packages that will be installed and the amount of disk space required are listed. When asked if you want to continue, type a “Y” (without the quotes) and press Enter.
When the installation is finished you are returned to the prompt. Type “exit” (again, without the quotes) and press Enter to close the Terminal window.
To use the Classic Gnome Desktop, log out of your session using the power menu in the upper, right corner of the top panel. You don’t need to restart the system to change desktop environments.
On the Log Out confirmation dialog box, click Log Out.
On the logon screen, click the gear button on the Password box and select GNOME Classic from the drop-down menu. If you don’t want any effects, you can select the GNOME Classic (No effects) option. Enter your password and press Enter to log on.
The Classic Gnome Desktop displays with the Applications and Places menus on the top panel and the bottom panel showing currently running programs.
On the Classic Gnome Desktop, there is no power button on the top panel. To log off or shut down, click on your user name and select an option from the drop-down menu.
When logging out, the process is similar but you are logged out automatically after 60 seconds if you don’t click Log Out on the confirmation dialog box.
Now, you can easily switch between the Classic Gnome Desktop and the Unity desktop. This gives you a chance to get used to the Unity desktop, but switch back to the classic desktop when you want a more familiar desktop environment.