To the OP, don't worry bro, you got a lot of terrific Trek to still catch up on!
TNG has a rough-ish first season but finds its bearings after that plus there are many nice cameos from TOS cast members. At its peak, it's a better show than TOS, of course TV had come a long way in 25+ years.
Deep Space 9 is worth checking out, it's a bit different and like TNG it takes a season or two to really start going, but it's more of a "War Trek" show once it really gets going and that's kinda cool.
Voyager or Enterprise weren't really my thing, but they're ok I guess.
The TNG movies missed their potential, but are still worth watching. First Contact is by far the best of the bunch.
I revist TOS and TNG and their movies all the time, there's so much Trek that you can always keep coming back to it.
