I grew up on classic. So this still ranks highest, surprisingly followed by Voyager - more or less it follows the same setup; meeting the unknown without backup (although the many holodeck episodes are rather annoying, an the repeated "almost-got-a-new-warp-core" wasn't that original either).
Enjoyed TNG for a time, but it got too artsy for me, with all that hairspray on Troy and the makeup on Data, and the general political correctness-attitude. DS9 was space soap for me all the way - and knowing a guy that just WAS Dr. Bashir didn't help much either. I haven't seen a lot of Enterprise, but what I saw didn't fit in with the rest. Nice, but not Star Trek.