If you're running 1.96, 2.0 should be something like a 5-8MB update...even on 56k, this should only take a half hour at most.
I'm under the impression hardpoint attach spots changed from DA to TA (something like that), so the short version is DA ships may technically work, but they'll look like shit. It's more likely they won't work, though.
I don't know if there's a converter somewhere, but I do know SD hasn't made one.
Ship creation works the same way, as far as I am aware-I don't believe there have been any significant changes to this since DL, except apart from adding new components.