The entire climactic Chase Scene. Wilby (in dog form) steals Buzz's car and goes after the spies, Officers Hanson and Kelly go after him and alert the chief of police that they're chasing a dog who's stolen a car, the chief of police tells two other officers to arrest them, Wilby steals Hanson and Kelly's car and completely bewilders the other officers... Hilarity Ensues doesn't begin to cover it.
That poor police chief. He thinks two of his men have suddenly gone mad, then he finds out their story is True After All.
Police Chief: Mercer, there are two loonies by the name of Hanson and Kelly masquerading as police officers. They're heading your way. Bring them in.
[shortly afterward]
Mercer: The mobile unit assigned to Officers Hanson and Kelly passed this point a moment ago. Hanson and Kelly were not in it, over.
Police Chief: Really? Well, would you kindly tell me who was in it?
A similar scene occurs with Stephano the butler. Francesca tells him to lock up "Chiffon" to prevent him from running away again. note Whenever Wilby is placed inside Chiffon's body, it vanishes from where it originally was and ends up in the location of Wilby whenever he transforms, therefore it appeared as though Chiffon had run away. He puts him the closet and locks the door, smugly commenting, "Let's see you try and get out of there." Wilby changes back into a human shortly after being locked in, and uses a screwdriver to get out of the room. Chiffon, who is no longer possessed by Wilby, wishes to play so Wilby tosses the screwdriver and runs while the dog goes to fetch it. Stephano returns to find the door has come unhinged and Chiffon carrying the screwdriver in his mouth, making it look as if Chiffon himself had opened the door with the screwdriver. He drops his tray in shock.
The start of the film, where Wilby launches a missile interceptor... through his house.
Wilby: Well, I guess we're officially into the rocket age. It'd be great to be up there with it, wouldn't it, Pa? [Wilson gives him a Death Glare] ...I wish I was on it right now.
Wilson talking about his time as a postman.
Wilson: Frieda, I am proud of the twenty years I've served in the mail service, and neither snow nor rain nor dogs ever kept me from my appointed rounds, but those blasted dogs tried!
Not to mention his reaction to Wibly wanting to take a girl to the dance.
Wilson: Now, Wilby's a little young to be switching from birds' eggs to girls, don't you think?
Frieda: Oh nonsense! Just because you didn't start dating girls until you were twenty-five...
Wilson: I wasn't twenty-five! I was twenty.
The 2006 film:
The Running Gag of Dave Douglas' next door neighbor's bulldog urinating on the former's front lawn, to Dave's chagrin.
Dave: Hey, Baxter! Why is it that my yard is that mutt's outhouse? Baxter: Uh, FYI, calling Attila a mutt is like referring to my Porsche Carrera as a Buick Skylark. Dave: Hey, look, whatever type of of car your dog is, I'd appreciate it if he wasn't whizzing on my shrubs. Baxter: You know what your problem is, Dave? You hate dogs. Dave: No, I do not hate dogs. I dislike dogs. I hate that dog! NOW GET OUTTA HERE! Baxter: (covers Atilla's ears) Stop that. You did not hear that, did you? You did not hear that. Are you OK? Baby?
The entire scene where Dave chases a cat in the city.
