"Emissary" didn't turn me off but for some time, until I'd learned to know the characters better, DS9 looked as TNG:s "minor team" if I should mention it in sports terms. The only characters who did make an impression on me the first time I watched DS9 was Quark and Kira.
But I must state thatTNG:s "Farpoint" was not worse or better. My reaction on that episode was something like "is that all there is?". After watching a few TOS episodes on re-run and the movies as well, I had expected more of TNG.
However, both TNG and DS9 did grow on me during continued watching during which I started to like the characters.
Voyager is the exception. I really liked and still like "Caretaker" and I took an immediate liking to all the character during that episode. The only one I did have problems with in the beginning was The Doctor but it only took two episodes before he became a favorite as well.
I became dissapointed with Voyager later on, in season 4 but that has nothing to do with the topic here.
In retrospect I think that TNG was the best made show and it did become better and better during the seasons, Voyager still remains a personal favorite because of the strong first three seasons and despite later misgivings and DS9 is a bit different but very good and entertaining.
But I must point out that I haven't watched all of DS9 yet, due to stupid policy of the station in my area in Europe which only did air the first season and due to later problems with defect DVD:s sold by Paramount in Europe.
More of that here:
http://www.trekbbs.com/threads/what-the-is-wrong-with-my-ds9-dvd-s.262327/
I still have 4 DS9 seasons to watch when I've sorted out the mess with the DVD:s.
I didn't watch TOS in order when I started to watch it but I guess that "The Man Trap" would have made me like it. I like that episode!
As for ENT, I never got into that series. After watching TNG, DS9 and Voyager in a row of years topped with TOS episodes as well, ENT felt like having a glass of lukewarm water as dessert after a magnificent dinner.