Well, here's how I'd rate it:
The good:
The Wrath of Khan -- this is really not overrated at all. This movie did so many things, that it almost seems impossible that it could be any good. It maintained the Kirk/Spock/McCoy dynamic, gave all the characters something to do, introduced a new character (Saavik), brought back an old character (Khan), and populated the movie with lots of other interesting characters. There are no wasted moments, no wasted characters, and genuine emotion. Still the best battle sequence, too.
The Voyage Home -- Walking a thin line between having fun with and making fun of the characters, this is still an enjoyable movie. As with the best of the movies, everyone is given something important to do. This movie strikes a really good balance among all its elements -- light hearted but genuine, socially conscious but not overbearing, and
First Contact -- The only good TNG movie. Good action, and hey -- how can you go wrong with the Borg? But some of it is leaden, and the Data/Borg Queen stuff was a rehash of stuff that we've seen a lot.
The Undiscovered Country -- the Shakespeare and cultural references are nice, but this movie is kind of a mess. A well-intentioned mess, granted. But many parts are weak (the trial, prison planet, and rescue) and the characters seem to be out of their groove. Spock has as many clunky lines as good ones, and as far as I'm concerned, the moment that Valeris was created as a stand-in for Saavik is the moment that Trek really started going to hell.
The okay: (aka entertaining, inoffensive, but lacking)
The Search For Spock -- This movie gets bagged on a lot because it isn't the Wrath of Khan, and never could be. There are occasional dumb moments, and much of the emotional core is lost with a wooden Saavik, but stealing the Enterprise and dealing with the planet and the Klingons are genuinely entertaining. Probably the movie that did best within its limits.
Insurrection -- A glorified TV episode, and inferior to many of the TV show's two part episodes. The love story, as with the movie as a whole, is flat, bland, and predictable. Not bad, but not good, either. Oddly, the movie is quite derivative of Generations, though nowhere near as bad. This would have been a forgettable TV episode, and the only reason it's remembered well is that it doesn't stink as badly as some of the other movies.
The Motion Picture -- This is long, boring, and often pointless, but it's not horrible. There's an actual story, and some characterization. V'Ger is actually quite remarkable, given effects at the time. But this movie could have used an original story and lots of editing.
The horrible:
The Final Frontier -- For me, it's hard to decide whether this or Nemesis is more embarassing. Nemesis was written by idiots, but in this movie, all the characters behave like idiots. There is no reason to watch this movie twice.
Generations -- Okay, I hate this movie. Stupid, lacking in plot, and a betrayal of characterization of both Picard and Kirk. Kirk was killed off for this movie? Probably the ST movie with the biggest lack of imagination, and biggest letdown from its potential.
Nemesis -- Where to start? This movie wants to be Wrath of Khan so bad, but doesn't understand what made that movie great. Plotholes, contrivances, and stupidities everywhere, along with pointless segments. Most of the cast is left out to dry, and Shinzon, while acted well, is a terrible character. The movie is a string of bad Star Trek cliches, capped off with the killing (and resurrection) of a beloved character for no good reason.
Stuart Baird.
I wish I knew what you're talking about.
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