I can generally find something to appreciate in highly regarded films so my feelings don't normally amount to detestation except for one film-- You Can't Take It With You.
A film that so delights in its own pretentiousness and "cleverness" is infuriating. Lionel Barrymore is of course the worst offender gleefully not paying his taxes because you know having roads and policemen is not his concern. One of the worst parts is that it has a cast, especially Jean Arthur and Edward Arnold, that could make it a much funnier film.
Day 3: Favorite Comedy
It's hard to go with just one, so I won't. Here are movies that could very well make up my top 5. Show People, It, Girl Shy, Trouble in Paradise, and Stage Door.