1 Minnesota Jones: Look, I told you there were dinosaurs here! {pointing at a small dinosaur, about the size of a cat}
1 Prof. Jones: I was expecting them to be big and fierce, pop.
2 [sound]: {the small dinosaur gets pounced on and eaten by a carnivorous dinosaur about the size of a cow} Crunch! Munch! Munch!
2 Prof. Jones: Now that's more like it!
3 [sound]: {the cow-sized dinosaur gets pounced on and torn to shreds by a Tyrannosaurus} RAAARRHH!! Crunch! Munch! Crunch!
4 Monty: Dad! Where are you going?! {as Prof. Jones runs away}
4 Prof. Jones: That Nazi prison sounds really nice about now!

2013-05-30 Rerun commentary: Interestingly, LEGO baby Tyrannosauruses are green, while adult ones are sort of blue-grey with red, white, and black stripes.

In truth, nobody really nows what colour Tyrannosauruses were, or any other dinosaurs for that matter. A good summary can be found on the Museum Victoria website [archive.org link]. I doubly recommend this page because, unlike most pages on the Web, it has exactly one reader comment, and it is brilliantly awesome.*

* It has since attracted other comments, but it's the first one that's awesome.