The expectation for the video component of the final debate is an original, well-organized, persuasive, professional argument video (PSA style) in support of your position for the assigned topic.
The requirements are as follows:
http://www.wikihow.com/Create-a-Good-Public-Service-Announcement-Film
(these are public speaking examples, but can be easily adapted and applied to video)
http://www.wikihow.com/Create-a-Storyboard
To shoot your video, you can use a digital camera or just a smartphone (Most modern phones have cameras that far exceed the required quality of what you will be filming). Film more than what you think you will need, but do not film too much content as it will lead to lengthy sessions during the downloading and editing process. The better organization you have going into this process, the more time you will save later in the production.
Use any video editing program to edit your video. There are several free editors from Microsoft Movie Maker to YouTube Editor as well as several free apps for your smart phone.