Give it a try though. The only way you learn these kinds of things is by doing it yourself. Once you learn the basics of this stuff you can apply it to other things.
A much easier solution would be to get two HomePlug powerline to Ethernet bridges. Plug one into the Ethernet port of the PS2 and one into an open port on your router. Simply plug the bridges into an electrical outlet and they are networked via your home's electrical wiring. You can get a kit with two adapters at amazon.com for under $70 and it a lot easier to set up than wireless.
Cable Modem-Router-Comp(UPSTAIRS) -Wireless Comp (Downstairs) and you cant run a Ethernaet to ur ps2 ..as they dont have LAN Connection on them ...take ur ps2 upstairs and put the cable modem direct to the usb port
I think that's what I'm going to end up doing.. it makes the most sense and is MUCH easier to set up. If you have anymore suggestions... just post. Thank you!