Ok, I found it. But your app stubbornly refuses to remember that I like "wide-and-low". If it remembered my preference, I'd be happy. EDIT: Oh, and if you make a settings file, maybe have a "start fullscreen" setting too?
Have you found a way to reduce the frames-per-second? Cutting the fps to 15 would probably improve the image dramatically, at the expense of some real-time motion responsiveness... Maybe another setting?