Throwing 2d10 of different colors is equivalent of trowing 1d100. It's nice they have different colors to avoid discussions, but you can throw them in two different bins or one at a time or something. Remember to sum them as (x-1) * 10 + (y-1) + 1, that is a clear indication of why zero-based indexing is better.

(Does someone sell "decade" dice, which faces say: 10, 20, 300, ..., 90 and 100?)

I would say yes, because the physics of rolling two objects is slightly different than one object. I don't have any idea, though, if that would affect the distribution of numbers rolled. It's not an experiment that can be done through simulation.