NAT Type on Playstation 3 (by 2 users)

I have a playstation 3 and a Zyxel p-600 series router. I think it's called port forwarding where I can make available the option for me to host games without loosing connection. a friend helped me configure a nat type 2 setting but I want nat type 1. how do I do it. I know theres a nuber I can put into the address bar and get onto the routers config/ set up but I don't know that number or what to do once I get onto that config page.
please help

Oisin

theoosh@hotmail.com