You don't want WEP. You just don't. WEP is easy to break (hack), slower (software encryption), and harder to remember (must use Hex rather then normal characters). Im pretty sure it defaults to WPA, so did someone install this for you? Let me guess, your ISP? For some reason policy is still WPA because older devices, and were talking early Wifi-G had difficulty with it. But any device since MS Vista hit the market will work fine with WPA. Some devices don't even work with WEP, like older Ipod Touch's.
But yea, takes Furry's advice.