[Pistachio is bald and wearing a huge, padded, rotund green suit]
Maitre'D: Are you members?
Pistachio: Not exactly, but... am I not turtley enough for the Turtle Club? Turtle! Turtle!
The scene in the movie when the villain laughs and then farts just out of no-where. Admit it, you smirked. This becomes a Running Gag. At one point, the villain gets through a laughing fit but doesn't fart. He's perplexed, then relieved at the lack of it, and begins to talk again, only to fart as soon as he opens his mouth.
Pistachio's training against the robotic slapping dummy carries at least one funny moment, when his family's usual threat of "Who's your daddy?" backfires on him and the dummy malfunctions to the tune of "I'm your daddy! I'm your daddy!" as it fights back and wins easily...
...but the real payoff comes after the credits, when after spending so much of the movie at the dummy's mercy, Pistachio somehow discovers the real "Slapping-Dummy Man" controlling the robot from the inside. Hilarity Ensues.
Another funny scene involving the dummy has it continuously pulling down his pants as he tries to hit on Jennifer, even making laughing noises at him ("HA HA! HO HO! HEE HEE!")
During the end credits, in one outtake, Brent Spiner looks at the camera with the expression of "Why, why, why did I agree to be in this shit?!" It's not ironic, but genuine.