Get the Picture by far. My sister still gets a laugh at how unintelligent most contestants on GtP are, and she's seen every show probably half a dozen times since we got Nick GAS 2 1/2 years ago.
One of my sister's best friends in college was a contestant during GtP's 2nd season. She was a smart, great game player in all parts of GtP--questions, power surges, and in Mega Memory. (Thank you, Nick GAS, for showing her episode ad nauseum.) Her partner, OTOH, nearly cost her team the game and did cost the team a chance at winning Mega Memory, by answering both incorrectly and taking too long to answer.