That would take many examples of 2000 year old dinosaur bones (not fossils)
An earlier poster said that dinosaur fossils aren't really necessary to evolutionary theory. There is evidence that dinosaurs are recent (which is what started this post-war), including non-fossilized bones, bones with possible blood cells still in them, and archaeological records which indicate that humans lived with them.
Yes, I don't think that 2,000 year old dinosaur bones would kill the theory. They'd be extremely surprising in their own right - and would be the find of the century - but they wouldn't do anything to the theory.
What would harm the theory of evolution would be finding 2 billion year old dinosaur bones, or 20 million year old Homo sapiens bones. It's when you find something that's much older than the theory says it must have split off from its "parent" species that threatens to upset the applecart.