Like prettymuch all romantic comedies, Futurama wastes time taking itself seriously and trying to make its character sympathetic and only afterwards fills in the cracks with a joke or two. Meanwhile, Family Guy is one hundred percent pure comedy, and the style in which most of the jokes are presented (character makes a reference, immediate cut to the object of reference, comedy, immediate cut back to the setting at hand) is incredibly effective.

I won't bother with The Simpsons since it's been irrelevant for years.