Melville Shavelson's Academy Award-nominated "Houseboat" involves the common trope of "vivacious-but-goofy woman turns serious man's life upside down" (also seen in "Bringing Up Baby", "What's Up, Doc?" and "Something Wild"). But how can you not love seeing Sophia Loren onscreen? Cary Grant's State Department employee is the archetypal man from the 1950s: straightforward, always wearing a suit and tie, and expecting everyone around him to be as no-nonsense as he is. The '60s were a reaction to this attitude.*
Admittedly, a lot of the movie shows its age. Many of the family interactions are too cute for my taste. The movie's real joy is seeing Sophia Loren in some of those revealing outfits (well, as revealing as was allowed in 1958). It's not any sort of great movie, but enjoyable enough for its length.
Watch for Murray Hamilton (Mr. Robinson in "The Graduate" and the mayor in "Jaws") and Kathleen Freeman (the nun in "The Blues Brothers") in early roles.
*Tuli Kupferberg of The Fugs was of the opinion that there was always reason for optimism, because, as he put it, no one who lived through the '50s would've predicted the '60s.