How much memory does a movie take up on an iPod will depend upon the size and quality of the movie. Assumedly, the movie has already been downloaded to your laptop or PC. Locate the film in your computer files. Right click on it. A box will open with "Properties" listed at the bottom. Within the "Properties" box will be found the exact size of the movie file. Programs such as Roxio Movie
. Creator (www.roxio.com) allow one to convert video files into less large formats.