Questions from a newbie

I bought the WRK54G with USB adapter kit at Sam's, not realizing there was another model. Would I be better off with the WRT54G? I can still take back and exchange. Reason for asking is this:

I don't have option to turn firewall on or off (so don't know if router is
on firewall) and no access restriction tab on the set-up page so I can
control/monitor the other pc. I would like to have those features which I
assume you can get in the WRT but not the WRK, is that right? If those
features are available with the WRK how do I get them/turn them on?

I am set up and running, one computer on adapter and one computer on router, both running Windows XP w/SP2. My Internet connection is via cable modem.

I have WPA security enabled, SSID broadcast disabled. Don't know
anything about MAC address filtering and what to do there. Running Zone
Alarm Pro v4.5xxxx on both pc's. Is there anything else I need to know? Am I good (SAFE) as set up right now?

Any and all help is greatly appreciated.

Thanks for the quick response and I figured as such. :cry:

What would be the main reason for switching? In the meantime is the set-up I described in my first post ok for now until I can get changed out?

Thanks again for the reply and help.