Did you download the latest version? Sounds like maybe you have an older version where some of the menus had a mix of English and German. If I were you, I'd uninstall the Goober you have now, then reinstall. You can get the latest version of Goober here:
http://goober.com/ I think when you install, it will ask what language you want. Choose English.
In my Connection screen (under Settings), it was already filled in when I installed Goober. For Proxy type it says HTTP. For Host/Port, it says 3128. At the bottom of the screen I see two buttons: on the left is Cancel; on the right is Save.
Hope that helps