Search for the movie using Movieclips. Movieclips is a movie database website in which you can search using different guidelines, including actors, genre, mood, setting, props, and dialogue. Type in details about the part of the movie that you remember, such as where it took place or what happened. The search will yield information about different films, including video of scenes and quotations. For movies with scenes not yet on the website, it will present other information about the film to jar your memory.
Search for the movie using the Internet Movie Database. Knowing an actor, screenwriter, director or even trivia about a film can yield a wealth of information on IMDb. Go to the homepage and type what you know about the film into the search box. Categories that you can search by include actors, characters, quotes, plots and even an advanced search. The search can yield biographies and synopses. If the search yields a biography, search through the work to find a title or synopsis that sounds familiar.
Ask the clerk at your neighborhood movie rental place. Movie store clerks can be notorious cinephiles, often known for their encyclopedic knowledge of the silver screen. Case in point, Quentin Tarantino was a video clerk before he started writing and directing films full of cinema trivia. As long as you can give them a couple of key details from the film, they usually can figure it out for you. If they do not have the answer for you right then, they can probably figure it out eventually amongst themselves as a matter of pride.