Heartwarming in Hindsight: For most of the book, Dad's regimentation and everything for the children comes off in a joke-like manner. Then, in the last chapter, the narrator tells us that Dad knew he had a bad heart and created all these organizational tools partially to help his wife after he died.
And as noted under Designated Villain, his actual intended Moral Event Horizon is not that he doesn't want children in the future, it's that he doesn't even care enough about the children that are alive now to help search for a missing one.
Alternative Character Interpretation: Is Tom selfish for having accepted a job opportunity that required them to move to a new city and into a new house away from everything they have grown up with and away from their friends and neighbors? Or did he genuinely believe accepting the offer and the job would benefit not just himself, but their entire family for the better in the long run and received no thanks for it?
Is the children's reckless behavior around the house after the move justified due to having been required to give up everything to support their dad's choice? Or are they a bunch of Ungrateful Bastards who refused to make the best of it and instead elected to express their disapproval through selfish rebellion?
Hank: is he just a silly guy who needs to bring his ego down several notches and understand kids aren't as bad as he thinks, or a fullout Jerkass who deserved what he got?
Charles: just your typical teenager facing real issues such as bullies and separation from his girlfriend, or a moody Jerkass who is rude and ungrateful to his father (going as far as to go off about Tom's competitive relationship in high school with his boss, whom Charles is barely ever near) does a poor job dealing with bullied, doesn't care about his siblings, and only apologizes once he knows his father will admit he was right?
Broken Base: People either think the movie is decent, think it's mediocre, or think it's so bad that they don't want to remember it.
Designated Villain / Informed Wrongness: Nora's boyfriend. He isn't fond of children, and appears to be quite awkward around them. This of course makes him a bad person, and we're supposed to find it funny when the kids play pranks on him that could seriously hurt him (setting him on fire, making him trip face first into a paddling pool, etc). Even the parents don't seem to treat it as seriously as they should, it's no wonder he's not fond of the kids if they act like little brats to him.
He isn't treated as a bad guy for that by the parents of his fiance, they both are mad at the kids for it. She only leaves him when he refuses to go look for Mark, who at that point in the film had ran away, just to watch his own commercial. Even with the way the kids treated him that's still wrong not to go look for your girlfriend's younger brother.
Funny Moment: In the sequel, Tom comes to his son's aid when he's harassed by some jerkass teenagers by speaking fluent Jive Turkey at them and leaving them dumbfounded.
Hilarious in Hindsight: Given the overlap in demographics between Smallville and Supernatural, the scene with Jared Padalecki and Tom Welling can be quite funny to watch. Plus, given that Jensen Ackles was on Smallville at the time...
Tastes Like Diabetes: The ending of the first movie. So sugary sweet that you'll end up getting cavities.
Tear Jerker: The treatment of Mark in the 2003 film, as well as the death of his frog that no one really cares about.
Kate mentioning growing up without her only sister who passed when she was still young.
Two moments in one. Immediately after the Exiled to the Couch moment between Kate and Tom, Jessica appears in her dressing gown and asks Tom if he and Kate are going to divorce, due to the arguing between them ever since Kate arrived home. Tom wordlessly picks her up and hugs her. Then Kate appears and reveals Mark has run away. But that's not the worst part. The worst part is Mark's note, which reads "Big families stink!!!" Shows just how unhappy and overshadowed Mark felt he was.
They Wasted a Perfectly Good Plot: Not a plot, per se, but after the movie theater scene in the second film, we're only shown how Sarah reacts to her father's embarrassment. One could wonder how Eliot felt about his father embarrassing him, since it is never shown.
Values Dissonance: When the mother leaves the children with their father for the duration of a short work-related trip, everything goes to hell due to the father's inability to take care of his family. The ending has her realize her mistake and promise never to leave the children again. This is a bit jarring to viewers from cultures where women are expected to work and fathers are expected to participate in childcare. (It's also the exact opposite of the original book, where much of the entertainment value came from the father's many unique and amazing methods of organizing the family's life to make it run smoother. Which worked. Of course, him being a workplace management researcher and everything.)
It can also clash with the values of some people that stereotype people with way too many kids as welfare-drains. While the Bakers don't seem to have any trouble providing for twelve kids, Tina does subscribe to the theory that no one should have twelve kids.