Copyright; Legal and Ethical

Copyright refers to laws that regulate the use of the work of a creator, such as an artist or author. This includes copying, distributing, altering and displaying creative, literary and other types of work.
For a copyright to apply to a work, it must be an original idea that is put to use. The idea alone cannot be protected by copyright. It is the physical use of that idea, such as an illustration or a written novel, that is covered under copyright law.

Three examples of different things which you might include in your video and could be subject to copyright:
Music
images
videos

Two webites that give free copyright music:
http://www.akmmusic.co.uk/
http://www.benedict.com/

Website where you can find free or low fee photographs:
http://www.photographywebsite.co.uk/copyright-in-photography-c494.html

what a location release form and why is it needed for filming:

You need permissions to shoot anywhere that isn’t either a) the street or b) a property you own yourself. If you want to shoot on the tube, in a hospital, in a club or bar etc remember to leave enough time for your filming request to be processed. These sorts of locations will ask that you put up signs to say that you are filming and that you get release forms for people who appear in shot. You should keep a signed letter of agreement from any location you film in.

What a contributor release form and why is it required:

A contributer release form is for anyone that has the skill or talent to join a part of a film such as, an actor, editor, camera operator and many more. this is done by signing the contributor release form to join however, if its not signed then the person would not be able to take part.