This program simply allows you to zoom in the video to get rid of the black bars on a widescreen movie, any other "features" it brags about are useless. This is NOT worth the money whatsoever. There is no point in even downloading it unless you can't stand the black bars. Then there is the fact that just zooming in on a movie doesn't really work. Since you are just getting the center of the wide view, you miss things that happen when the camera is not pointed directly at them, which is fixed when the movie companies convert a film, since they select the most important part of the frame and zoom in on that. If we watched all movies in just cropped 4:3, we would have a very interesting time dealing with half-faces and strange parts missing. If you just want to play a movie full screen then download VLC, MPlayer or any other alternative, if you really like quicktime and want to play a movie full screen the compile this code in Script Editor and run it as an application when you have a movie open in Quicktime.
tell application "QuickTime Player"
Save it as an application and then simply run it with any movie open in Quicktime. Its that simple.