I currently have a private wired network and want to add public WiFi, on a budget, so I do not want to purchase any new equipment. My internet comes in to our modem and goes to a generic wired router. Only 3 or 4 machines are then off of that with a couple of printers. Now I have a WRT54G that I would like to utilize for a little public wifi, no more than half a dozen people would ever be on at a time. What I want is so the Public Wifi will not have access to our private computers or printers. How best would I go about this? Thanks.