I've recently rewatched most of the Star Trek movies (just the TOS & TNG ones, not reboots), and had forgotten how amazingly good some are, and how ridiculously bad others are... made me remember a bit from Futurama "Hey, ya know what 6 movies equal out to 3 really good movies? The first 7 Star Trek movies."
Star Trek, the Motion Picture -

favorite, hands down, but I like a good cerebral story. Least action of any of them, probably, but some of the best space panorama shots.
The Wrath of Khan - also a damned fine story, and amazingly well done, imo. Nice balance of story & action.
Search for Spock - holy plotholes, Batman. On the fence with this one, overall highly watchable, but disappointing after the first 2.
The Voyage Home - WHALES! And TIME PARADOXES! Pretty meh, don't care for it. I'm rather alone on this though, so take that as you will.
The Final Frontier - No. Just no. Silly and ridiculous don't begin to describe this... thing.
The Undiscovered Country - ok, this is, imo, the single best of the TOS-cast movies for an action flick. Pretty good, overall, though it has several weak points.
Generations - meh... less of an actual movie, more like a grandiose announcement they will be switched to the TNG cast going forward. Overall watchable, but very lacking, comparatively.
I'll see about doing the other TNG movies after I finish them.