logging in as root

Hi, I followed the instructions to add a password to login as root.
How does this work at the login screen. Typing root pressing inter and then 
entering the password doesn't work.
Using my login name and the root password didn't work either.
So how is this suppose to be done.
Thanks Mike.
X-Antivirus: avast! (VPS 000742-0, 05/21/2007), Outbound message
X-Antivirus-Status: Clean