This tutorial will explain how to enable the root account on Ubuntu (12.04/11.10/11.04 or older). A default installation of Ubuntu doesn't allow users to login to the root account, however, you can have root privileges by placing "sudo" or "gksudo" before the command you want to run via the terminal:
If you want also to browse your files and folders with root permissions via the Nautilus file manager, you can use this command from the terminal:
Enabling The Root Account
By default, the root account is set with no password. To be able to login to your root account, you need first to assign a root password. Launch the terminal (Ctrl+Alt+T) and run this command to enter a new password for your root account:
sudo passwd root
You will be required to enter a password two times. If everything goes well, you will get this as outputs:
Enter new UNIX password:
Retype new UNIX password:
passwd: password updated successfully
Logout the current session and in the login screen, click Other and login using "root" as username and the password assigned:
The root session will now start.
Warning: For security measures, it's not highly recommended to enable the root account. So, use it carefully because any misuse may render your system unusable.