While this isn't necessarily the comedic masterpiece that is "Airplane!" by the same director trio, it's vastly better than any of the parody films that you find these days (think "Scary Movie"). If you think Scary Movie 3 and 4 are the best ones, for instance, then that's because one of the three directors behind "The Naked Gun" was behind them.
However, this movie is from the early days of hilariously clever parody movies, back when it wasn't necessary to throw an insane amount of pop-culture references in the mix to keep the movie funny. Many of the jokes here are among the best in cinematic history, and stupendously genius in their stupidity. It's like taking the "Yahtzee!" joke from Scary Movie 3 and spreading it throughout a whole movie. Admittedly, this might defer to slapstick humor a few times too many, but that's part of the fun, really. The movie has aged surprisingly well, regardless.
Essential watching for anyone who has the ability to laugh.
In a sentence:
Flat-out genius moments amidst a completely silly and hilarious movie.