Got a screenshot? Also, what's your resolution? I don't get any distortion at all, but my monitor is a 16:10 monitor, which is what the system defaults to.
It's set up so that it can use 4:3, 16:9 and 16:10 aspect ratios, and will try to auto-detect what your screen is set to on start. If your monitor isn't at one of those aspect ratios it will default to 16:10, with a resolution of 360x225, pretty much because that's my default ratio, but you can easily change it to whatever and also add in more conditions to auto-detect other ratios. I only put in support for what seem to be the 3 most common ratios, so that might be one cause for your distortion. Of course it could be something else entirely, but I'm not much of a tech guru so it could just as easily be graphics card related.
But yeah, a screenshot and resolution settings might help work out your kink.