It starts slowly, showing the dreary lives of the two housewives who decide to rent a castle in Italy for the month of April, but don't give up on it. Nothing much happens, but the time passes exquisitely, and there are numerous sly jokes (my favorite is the carriage ride in the storm, which I find hilarious). The movie is wonderfully romantic in many senses of the word, the scenery is beautiful (as is Polly Walker), and the resolutions in the movie are very satisfying.
The movie takes a couple of liberties with the book, the biggest being with the Arbuthnot/Briggs/Dester business, but I actually preferred the movie's version of this (it may be more sentimental, but I felt that it was more consistent with the tone of the story, and anyway I like sentiment when it's well done).
An excellent movie, especially as a date movie during lousy weather.