I like adding information about the movie (i.e. meta data), and I use MetaX to do so:
Apart from Title, Artists, Genre, and other usual information, Metax can
also add cover art and set a content rating on the movie. (It uses a modified
version Atomic Parsley to write the tags.) I can then use the iPhone's
Restrictions setting to avoid a child (or anybody else) seeing
I can then set up the iPhone's restrictions to show films that are, say, PG 13
and movies rated above that are no longer displayed on the iPhone or iPod.