Welcome to the forum smorton.
Putting a movie on the hard drive isn’t exactly burning—normally you rip the movie from a disk or download it from the net. It is possible to edit this copy on the hard drive.
What format is this movie in? Is it a dvd-video or an avi file or what? There are different tools available for different formats, though some can work with a wide variety.
If this is a dvd-video you can use DVDShrink in ReAuthor mode and use the Start/End Frame tool to select the exact section you want and save it as a small dvd-video. DVDShrink is free to download and use. Just click on the word DVDShrink in the previous sentence and it will take you to the download here at cdfreaks. You can find guides for using it at www.mrbass.org and www.dvdshrink.info
If the video is another format, you can use AviDemux. It is also free to use. http://fixounet.free.fr/avidemux/ Read the instructions in their wiki: http://www.avidemux.org/admWiki/index.php?title=Main_Page