most routers will have a wep key under the router....unless you set it up with a custom wep key.
Your default WEP key is a 10-digit number below a barcode under your 2Wire mode. The other number there is not 10 digits, so it's easy to tell which one it is.
If you changed the default key to something else then try going to http://192.168.1.254 . This is your gateway's admin page where you can retrieve the WEP key.
And please, don't reset your modem. That would be unnecessary extra work.
If you detect more than one wireless network like the ones on your pictures, that means one of your neighbors also have a 2Wire. The default SSID is 2WIRExxx where xxx are the last 3 digits of your gateway's serial number (also under the gatway itself).
To find your WEP key go to a computer WIRED to the gateway, go to the 'command prompt' under 'Accessories' and type IPCONFIG. This command will give you the 'default gateway' address, which should be something like 192.168.1.254 (see link above).
Now, type that IP on your browser and browse to the wireless settings page. You may need a password to access these pages. If you don't have it you will need to call your ISP or reset the gateway and use the default WEP key on the sticker under the gateway.