Buffalo Router Set Up...Need Help

Hi, I have a Buffalo WHR-HP-G54 Wirelesss Router that I'm trying to set up for my home network. I had a borrowed LinkSYS, and need to set up my own. I have used a similar router with a PC network at work, but for the life of me I can't figure out how to set up...Some info I've seen says it will 'automatically' set up...sure I have a G4 Mac Mini (no wireless, running Panther) that was the primary set up computer, but now have an intel iMac (running Leopard) as well as a variety of clamshells and imac G3s for the kids (running Panther and Tiger). I'd like to have the Mini hard wired in via Ethernet and all the others airport wireless...Any and all help greatly appreciated, I've just not been able to find any clear instructions on configuring and setting it up yet, although most info says it can work very well (am I mistaken?)..Thanks, Rick