Change the SSID (Wireless network name to one you know) and for the sake of testing set a simple WPA key initially e.g. 12345678
Then see if the devices will connect to this new network with the new easy settings, if so then set a better WPA key (i.e. one that is hard to guess) and carry on.
Avoid characters like - . ! | spaces, stick to letters and numbers.
if you cannot still connect, check that the router is accepting 802.11g connections, and if a N device that it is operating in a 20 / 40 MHz mode, rather than a pure 40 MHz mode.