I have a Droid, and yes, you can copy & paste, but not in the body of an email that was received. And Yes I can send an email to multiple contacts but you have to enter each contact in one at a time, you can't go to your contacts list and check off a bunch of contacts at once.
I did however find out how to create and actual "Group" using the Droid...since Group contacting does not transfer over from Gmail to the Droids Gmail.
I already posted on a different thread how to create groups...search: "Creating Groups"...look for my post...its a pain in the a** though.