As for the downtube dent, i would ride that. If it were me, I would take a look at the rear chain stays and look at the factory crimping that is done there for tire and chain clearence and then compare that roughly to the dent on the downtube. I bet you will see that the factory crimping on the chainstays is more than the little dent on the downtube.

I'm no expert but that is how i would rationalize it.

As for the fork, I might try to find someone who could straighten it but if not, I would look for a complementary color fork and replace.