I too think this is a tough one, one that gets complicated by "external" factors, ie, when you saw it, the death of a character....
I saw TMP more times in the theater than any film, mebbe 9 or 10 times, cutting school once to do so. I love that film dearly and watch it almost every Dec 6th, but...
It is a rather flawed film. The music, the epic start, the first 15 minutes that blew me away... and then grinds to a halt as soon as someone speaks (English) in the film. None of the character traits that made TOS, odd pacing, bad acting.... No mattter how much I love it, it's not a good movie.
I'm opening myself up for some grief here, but by the time 1994 came around, I was a bigger fan of TNG than of TOS, especially how the "classic" movies had distorted TOS into comic book plots. (I maintain that "Search for Spock" was the first "real" Trek movie, with the 'scifi" of TMP and the characterizations of TWOK, and I will take you all on in a bunch or one at a time to prove it!). What was great about Generations was that... it was an episode, and I mean that in a complimentary way. There was no "let's get the crew back together," no "this madman will destroy the Earth/universe," just the good ole Big E, out doing it's thing, getting in trouble. Characters have arcs, some people interact, the bad guys has their own agenda... I liked how one Captain was pining for the family he never made time to have, and the other Captain wondered if he shoulda stayed in the cabin with his dog and woman. In the end, I think I was sadder to see 1701-D go that Kirk, only because his time had pat and at least he went down fighting.
In truth though, Generations is not a fabulous film either. Coulda done more with Kirk in the future, that Nexus certainly was a convenient plot device, and geez, looked mostly like a TV movie...
So, I'm going to go with Generations just barely, if only to stick up for TNG, (including Whoopi
). And to disagree with you slightly 762_XC; I agree that the TOS cast was looking campy in ST4-6 (especially 4. Ugh), but I think Generations redeemed them. Say what you will about Treknobabble, but to hear Scotty come up with a technical answer and Chekov to act other than "funny sunding Russian guy" was a treat. It's a shame that most of the TOS cast bowed out; that bridge scene would been more like a TOS episode than anything since Turnabout Intruder.
And give credit where credit is due... Sirgod, these are some good polls you've got going... very challenging and discussion-provoking!