Hi Geoff Don't know if you read my post regarding your problem. I just tried altering my interfaces file in the same way as you. It killed my wireless. I'm convinced that you should restore you interfaces to the default. I'm sure that you can use the wpa supplicant gui program to configure WIFI even...

Hi I think you should try and set your interfaces file back to the original configuration. The gui wifi setup progam uses the /etc/wpa_supplicant/wpa_supplicant.conf to store the wifi information even if you are using wep. I also think you should reboot your PI after you have used the gui wifi setup...