Note: When searching the Main Catalog or an article database for sources about film, combine the terms motion pictures OR moving pictures OR films OR cinema OR [talkies, Bollywood, or any other appropriate words for your research].
If you are looking for videos owned by Princeton, use either the Books+ or the Main Catalog search interface. You can limit by format once you view the result list. Videos and DVDs are most likely to be housed in the Humanities Resource Center (011 East Pyne) or the Mendel Music Library (for an opera production, for instance).
The Princeton Public Library, 65 Witherspoon Street, has a large collection of films as well. Go to http://www.princetonlibrary.org/ to discover what they have.