Oh, in regards to SERIES, Deep Space Nine is the best, hands down, for me. The depth of the stories, especially Seasons 5-7, and the serial nature really appealed to me.
Characters died, things in one episode affected things in the next, it was great. Oh, and it had actual relationships. In TNG, the closest thing to an actual relationship was Riker and Troi playing high-school girlfriend/boyfriend. Hardly compelling stuff.
In DS9, you had interracial and interspecies relationships, you had realistic conflicts and fights, even death and dealing the aftermath.
Also, the best fights. Space battles that exceeded the mark set by Return of the Jedi, like Babylon 5 did too in the same time frame.
Enterprise was just starting to get good, and seemed to be setting course in that direction. Too bad.