Alright, I edited the Widescreen value in settings.db which removes the black borders (and stretches the default skin to fullscreen). I made a full screen skin so it wouldn't be stretched out on a 4:3 screen. I figured this would do the trick but it didn't quite work as planned.
First, I edited Aurora_Main.xur: I changed properties from 1280x720 to 1280x960 (so from 16:9 to 4:3), then changed all the individual properties of all the elements in the skin to 1280x960. For some reason the whole skin gets shifted to the right. I will post pics of this later. I think is has to do with the widescreen fix, because without editing this value, the skin is nicely centered in the middle of the screen.