GIMP-y

So I've been using The GIMP to create a comic (check it out here). The thing is though that The GIMP has been slightly annoying me in certain aspects. Especially the rectangle selection tool. Now I will admit, I am no GIMP guru. There just isn't really a simple way to create shapes with it, at least not that I'm aware of, so I've used the rectangle selection tool, which while successful in some aspects I also seem unable to unselect the stinking thing. So then if I try to do something outside of the previously selected area I can't do squat. It just irks me...ok vent over.