I have a wireless Verizon network at my home, just set it up too.
To play the Xbox online, you must buy some sort of adapter. The official one runs at 99.99, and all others I've seen are in the same range. The official adpater is VERY easy to set up, like less than 5 minutes to do so if your network is up.
I'm not sure aobut the PS2 though.