A film is made up of different types of copyright material. The film itself may be protected by copyright, and the music, screenplay and other materials used in the film may each have separate copyright protection.
Make sure any DVD you play is not an infringing copy.
Reference: Australian Copyright Council. Information Sheet: Films, DVDs & Videos: Screening in Class. Retrieved from http:// http://www.copyright.org.au/
For more information please see the following Australian Copyright Council Information sheets: