A family film is a film that has been carefully written, directed, acted and cast so that it will appeal to the common members of a family:
Perhaps the clearest recent example is Beethoven (1992).
It has a big cute dog named Beethoven that continually performs minor slapstick comedy on the father and mother. Also, the dog gets in trouble that is simple enough for the smallest child to understand.
The father has business problems, briefly but thoroughly developed, with silly side-lights to keep the children from being bored.
The teens love the dog and resent their unfeeling father.
The mother has relationship problems: The father hates the dog, the children want the dog and feel unloved, the mother has to make peace, keep the house clean, the kids fed, the husband loved, and remain lovable.
The problem is resolved when the father accepts the dog, and rescues him from the evil mad scientists, with the help of the family.
Thus, the dog stays happy, Father remains king of the hill, (very satisfying for both adults and children), and the relationships are healed, solving the mother's problems.
Such films include: