I'm going from memory:
Season 1:
Winner: 11001001
Honorable mention: Home Soil
(Both are neat sci-fi classics, with the latter being TNG's most "hard sci-fi" outing. A close third is "The Arsenal of Freedom" as it's a great Geordi episode and an example where the ship can pop its top to separate and the drama doesn't fly away as a result.)
Season 2:
Winner: Q Who
Honorable mention: Elementary, Dear Data
(Season 2 has
many stories to highlight; about seven vie for the honorable mention position. "Q Who" just nails everything with the Borg threat and Q's antics, but "Elementary" comes very close as it is a top-notch Data/Geordi/Pulaski episode loaded with great scenes and great casting. Daniel Davis excels as Moriarty, and the exploration of Data being more than the sum of his parts definitely wouldn't have gone anywhere in season 1. I can't begin to see this episode with Dr Crusher being abducted, much less questioning Data's abilities.)
Season 3:
Winner: The Best of Both Worlds
Honorable mention: Hollow Pursuits
(Season 3 definitely has a number of greats and the race between top two spots is very narrow. TBOBW seems inevitable for its action fare, not to mention how easy cosplay is now since anyone can buy plastic plumbing hoses and cat laser toys to tie onto their heads for real cheap, but "Hollow Pursuits"', which was not poking at sci-fi nerds, was showing a new issue and new character and not in a condescending way. )
Season 4:
Winner: The Best of Both Worlds pt 2
Honorable mention: The Nth Degree
(The plot reversal of TBOBW is more than inspired and, IMHO, is one of the few times when pt 2 even rises above pt1 overall. As for the honorable mention, TNG always had a knack of introducing characters who aren't in the bridge clique and end up being more memorable. The Barclay/Geordi relationship being not quite as good as Geordi/Data, but it's high enough to really enjoy.
Season 5:
Winner: Ensign Ro
Honorable mention: The Next Phase
(Any Ro/Guinan scene never fails to steal the show and I adore Ro, but her premiere ekes out as being arguably the strongest story. "The Next Phase" may have woofy science, yes yes, but the philosophical underpinnings and Romulan guile more than make up for it and the writer of the story knew where and when to put the emphasis to get audiences to keep the suspension of disbelief going stronger and longer than the battery bunny cat toy. Even the music is on par, something season 5 was so uneven on. And, of all the characters who come in who aren't cliquey, Ro stayed the longest. )
Season 6:
Winner: Ship in a Bottle
Honorable mention: True Q
Honorable honorable mention: Descent pt 1
(This season is one I don't remember much of, save for too often the bad episodes or misfires. Ship in a Bottle -- there's never a Barclay episode I couldn't like, and this one just hits perfection. Plus, Moriarty had an ECC checksum error and that's how he doesn't remember his desire to full Dr Pulaski with his crumpets but instead has a new fling as character foil. True Q makes a terrific allegory, despite some uninspired parallels to "The Wizard of Oz" that seem more unbecoming to TNG's script quality up to this point. On, the tornado from Kansas and why not just rename Amanda to Dorothy and be done with it? That said, it broadens the Q realm a lot, and the Q/Crusher scene is great on multiple levels. As for Descent pt 1, it starts with potential (even if the music is uninspiring) and enough to like that, despite it all, it deserves an honorable honorable mention. Especially when something like 70% of the season hasn't dated well. For me IMHO, YMMV, EIEIO. Hmmm, maybe the honorable mention and honorable honorable mention could be swapped, hmmm...)
Season 7:
Winner: The Pegasus
Honorable mention: All Good Things
(The good episodes really stand out because the show was burnt out and smell more than what I just saw my cat put into the litter box, what with everyone and the good plotting moved to DS9. Pegasus adds to Riker's backstory in a way that genuinely works, especially when rewatching older episodes. It fits. Add in Romulan guile but also the Federation reacting to it via the Treaty of Algeron, plus more phun with phasing. ATG is a great bookend and classic, and both are great, but the Pasteur shouldn't have generated the original tachyon pulse, so there.
)
And now I need to go clean the litterbox. That unscented pine stuff does nothing for odor control...