Yeah, it's hard to think of 1 as very good unless you played it when it first came out, like I did. At the time, it was a pretty unique game. Console RPGs of such complexity were a new thing, and FF1 was the first game to really blow the competition out of the water. It really was genre-defining.
Yep, although that said, the PS1 and GBA remakes are actually pretty good. Not GREAT by the standards of the time they came out, but much better than the original NES version, anyway.
For my order, I'm only counting "main" numbered series games, so no Tactics or any of that. Also not including XI since it's online, and excluding the games I have not played, which are II, III (Japanese numbering scheme), X, X2 (which I did play a LITTLE of, and it struck me as being pretty bad), and XII.
1) FFIV - the best storyline of the series, IMO - a great, "Tolkienesque with sci-fi" fantasy story. Gotta go with the improved translation of one of the remakes, tho... the original American SNES FFII would be a bit lower on this list.
2) FFVI (American SNES FFIII) - I don't feel it matters with this game if one plays the remakes or not. An amazing game with possibly the best pure gameplay in the series, and a story that's GREAT for the first half, but falls apart in the second half (the World of Ruin felt like a huge collection of side-quests to me).
3) Tie between FFVII and FFVIII - I find the former overrated but still excellent, and the latter underrated. Though there are still things about it I find irritating (more on that in a minute).
4) FFV - The job system is a blast, and this game has a lot of humor, but I find it suffers for having the most straightforward, predictable, and simplistic storyline of the "post NES era" FF games (IV and beyond, basically).
5) FFI - It defined a genre and was groundbreaking for its time, but
definitely play a remake if you can. This game does depend on nostalgia more than any other game in the series to remain good, though.
6) FFIX - Yes, I rank it below I. The graphics were nice (though a step down from VIII, I found) and the music was ok, but that's about it. Boring, convoluted story that had way too much trouble figuring out what it wanted to be, awful characters (Vivi was pretty cool, but everyone else was terrible), and some really annoying gameplay systems. A huge disappointment.
It's interesting to see how hot and cold people are to 8 around here. Even those who love it have things they hate about it! Personally, I like all its quirks. Yeah, the GF animations should be skippable, but I'm fine with replacing most equipment with magic junctioning instead. It really requires you to think of your magic as a finite resource, and I think that's why some people don't like it. The FF games have always had kind of a "bottomless gun clip" mentality, and 8 was a definite change of pace, at least when it came to magic.
It's funny, but I never minded the long-ass summons. The button mashing got annoying, but that isn't one of my main complaints about VIII. I found that I liked and hated aspects of both the story
and the gameplay. Loved the overall plot, hated how rushed it got at the end. Really liked some of the characters, hated the others. Thought the junction and draw systems were both good and bad.

Etc etc...
As for junctioning and magic, I didn't mind the idea of making magic more "limited" than in other games, forcing you to ration it. Nor did I mind that it was linked to your stats, therefore using your spells could lower them, forcing you to pick when it's worth it to do so. What I hated was that
none of that mattered, because all the spells in FFVIII were insanely weak. The "strategic choice" that could have come out of the junctioning system was moot, because there was NEVER a reason to cast a spell in battle, since they all sucked. There were far too many other (better)options for healing, and by the time you're not even halfway through the game, you can do FAR more damage with summons and even regular attacks than you can with any spell.
That really irritated me more than anything else in VIII.