There are several different "styles" of citation, and different institutions require you to follow different ones. There's "MLA" ("Modern Language Association,") "Chicago style," and about a dozen others. Before anyone can show you how to write out the citation, it is necessary to know which style you are expected to use. There is a "style manual" for most types of citation, usually available in a library, or you can find the formats for different types of references online. In the case of the videocassette, I would be tempted to cite the movie, not the cassette. In the case of the interview, there is, indeed, a format for this. Of course, you have to know which style you're expected to use; then you'll be able to look up the correct format.
