About rooting and original Firmware

[Guest Filipe Catalao]

Hi all. I have a new LG Optimus Black.

One question: I already used Android, with costum roms from were, for my old Zte San Francisco.

In this case, I want to use original Roms only, but i want/need a rooted phone for SuperUser permissions.

What can I do? I just need to Root? If I Root the phone can i upgrade normally to 2.3 (will be released soon),via LG update program? And can I use apps that needs Superuser acess or I need an extra aplication ?

Tks all