Linksys G Adaptor and OSX HELP Please!

Hi,

My grandparents just gave up on wireless internet so I got their internet stuff, which is a Linksys Wireless G BroadBan Router and a Linksys Compat wireless G USB network Adaptor with SpeedBooster.
My questions are,
How to get the Router to work correctly with two macs (imac g4-10.4 and a iBook clamshell-10.3). I plan to connect the imac using Ethernet and the iBook with the Linksys Adaptor.

Seconed question is how to set up and install the necessary software for the Linksys Wireless G adaptor. Will it work with Mac os X Panther?

Basically treat me like a 4 yr old, with lots of detailed step by step instructions on how to get internet with this stuff.

Thanks for any help!!
Craig