What's your favourite movies? for me it is, without doubt, ST-VI, and ST-VIII. I also like ST IX a lot, because of the relative calm in it and one of the most beautiful and moving scenes I have ever seen in ST (when Picard is being explained that learning does not need a lifetime and the Kolibri in front of him slows down in flight and finallly freezes in the air), and ST-IV, because it's queer humour.
STI, ST-VII are the most awful of them all.
Uh, and this: Spock rules!