Gulliver's Travels was the second American feature length animated film. While this makes it a curiosity for animation fans, and an important milestone in the history of film (even if most film historians would disagree), this doesn't necessarily make it an entertaining film for the casual viewer.
Part of this isn't the film's fault. Since Gulliver's Travels was a Fleischer production for Paramount, it wasn't accorded a "classic" status the way Disney's features were. The film did decent box office business at the time, but the Fleischer brothers were hardly beloved by Paramount and were fired from their own animation studio a few years later. Paramount had little incentive to preserve the film's integrity. As a result, many (if not all) of the copies in circulation on videotape are of horrible quality, and are on low-budget tapes. They are jittery, blurry, and have wobbly soundtracks as did many creaky Hollywood films discarded for broadcast in the early TV era. The film occassionally turns up on TV from time to time as well, virtually without fanfare. The poor quality of these copies make the film seem even creakier than it is; perhaps viewing a pristine print with a restored soundtrack would be a more favorable experience.