Ubuntu 11.04 Login with Root User

I know sometimes it is very easy for any user to do this, but I got something else that took my lots of time to get "root" access.

While using Ubuntu 11.04 I got an unexpected error i.e. "sudo: must be setuid root" and for this I need to login with root user but how as when I tried to login it is giving me the same error.

I read somewhere that for the above problem I need to start my system on Recovery Console, but how? As soon as I start my system it is taking me to GUI Login Screen.

Now to get access of "root" user follow the below steps:
1) Restart system by HOLDING SHIFT key.
2) While restarting press ESC key till you get the OS menu telling you for the recovery mode (Do not release the SHIFT key)
3) Now you are on ROOT user and do whatever you want.

Hope this helps :)