You do not want to make sure you are not using WPA-EAP.
It turns out that I was using a specified DNS server when I set up a static IP address for port forwarding for my u Torrent connection.
The only passwords I have are 8 capital letters and an 8 digit pin which was sent to me.
I have not had any problems connecting the kids laptops and i Pads or mobiles - just the older pc I have.
Assuming that you do not have SP3 installed, try to go into your wireless network configuration / configuration screen.
(There are several different configurations of wireless, including Zero Config, but we do not know that you are using).