Note that Movie Rotator can only rotate QuickTime Movies, which are stored in files with a MOV extension. If Your Camera takes AVI/MPEG/MPG or some other kind of video, you can't rotate them with Movie Rotator.
To rotate a movie using Movie Rotator, follow the Steps below.
Once Movie Rotator has installed run it by selecting it from the Start menu, or clicking on the desktop shortcut if you opted to Create a desktop shortcut during installation. Movie Rotator will then start up, it looks like this: