My three part list for the rest of the movie:
1. It is badly cast
2. It is badly acted
3. It is badly written
THE STORY: Dumb, clumsy guy meets rich girl, they fall inexplicably in lust, they get hitched, they have a lousy honeymoon (due to their own stupidity), they quarrel, they break up, they make up (repeat last three items several times)
The movie consists in its entirety of every bad, hackneyed gag best left on the cutting room floor. There is no on-screen chemistry between Kutcher and Murphy, and the torturous story limps along slowly and painfully to an unbelievable ending.
The old lady in the car speaks for all of us - this wreck of a movie should be put out of its misery.
Let me just point to too things in this 2003 comedy from directory Shawn Levy that shows why it does not work. In the aforementioned scene when Tom and Sarah are trying to join the Mile High Club, their attempts are funny instead of sexy. There is fumbling and bumbling, admits lots of laughter, and then the whole thing ends with the Nasty Stewardess (Jill Parker-Jones, and, yes, that is how the character is named in the credits) who has been banging on the door to get them to return to their seats getting her nose broken, a rather mean-spirited payoff to the scene. Then there is the uncredited Veronica Cartwright as Mrs. McNerney, who has a nickname that she insists Tom use when he becomes engaged to Sarah (I cannot put it here, even though it has five letters and not four). I waited the entire film for this nickname to have some sort of payoff beyond Tom snickering every time he uses it or hears the name, but nothing was forthcoming from Sam Harper's script, which is pretty much the problem with the rest of the comedy.
Cartwright is wasted in this script, as is David Rasche as her husband, but then everybody is pretty much relegated to a supporting role. It was great to see Christian Kane, who did some wonderful work on the television series "Angel," as Peter Prentiss, the guy Sarah's family wants her to marry, but he is also wasted in this film. There is a subplot where Peter refuses to take Sarah's "I do" for an answer and continues to pursue her, but it is pretty lame and just another "by the numbers" element of this film (which includes the happy ending).
There is a weak attempt to add some sort of class conflict to the comedy since she is the daughter of a rich family and he works for a radio station. But it has nothing to do with the story. Tom might not be stupid, despite some evidence to the contrary, but he has no trouble playing the Ugly American and he cuts a path of disaster through southern Europe. "Just Married" also tries to impart serious "lessons," in addition to the fact that you should have sex on your wedding night or horrible things will happen. The main lesson is that you should confess your sins (e.g., he sort of killed her dog) to your spouse so that you marriage is not build on lies. Having something to talk about besides sex and not insulting Europeans because they are not Americans would be better lessons, but this film is not interested in aiming anywhere near that high.