TOS is great, except of 99% of the third season episodes.
TAS - a couple of great episodes, a couple of horrible episodes.
The Motion Picture - a very long episode pretending to be a Star Trek version of A Space Odyssey
The Wrath of Khan - excellent movie
The Search For Spock - only good segments are the comedy scenes on Earth and the destruction of the Enterprise, the rest is shit
The Voyage Home - brilliant movie
The Shatner One (I can't remember the name right now which clearly shows the impact it had on me ) - a few good scenes, a lot of really bad scenes horribly edited together
The Undiscovered Country - another brilliant movie
TNG - slow start (in these days it would be canceled during the middle of the first season), but it gets better and better, the last 3 seasons are just brilliant
DS9 - unfortunately I started to like the show only after they came up with the Dominion war, which is kind of sad
VOY - crap. I never liked it. I mean 7of9's boobs are nice to watch, but the rest? A bunch of shitty stories about uninteresting (and a lot of times annoying) characters
ST Generations - crap which makes absolutely no sense. I don't know why people claim the Shatner One is the worst Trek movie, this one is much worse.
ST First Contact - a great fun sci fi action flick
ST Insurrection - a very long episode. Not bad, but not exceptionally good either
ST Nemesis - horrible piece of shit which makes absolutely no sense at all
Enterprise - I liked the first season, a couple of second season episodes, and the third season. Season 4 was absolutely horrible, and I was shocked to find out how many people claim that it's the best one.
Star Trek : The Star Trek - horrible piece of shit which makes no sense at all. The only thing I liked was the main music theme
Star Trek Into Darkness - a much worse rip-off of Wrath Of Khan. But at least it's better than JJTrek, I could enjoy it as an action movie (but not as a Star Trek movie)