When I had Jaguar I opened the root. Everytime I logged in a user named other appeared. however when I upgraded to Panther it was gone. What can I do to get that 'other' user (the root) again?
If you enable root user as given in the website above the "other" user will appear as a log in option.
That said, you should never treat root as a normal user. Only log into it to do specific administrative things when you know exactly what you are doing. There is nothing that root can do that typing in the admin password can't.