Honestly I cannot personally recommend any Final Fantasy game as none of them really appeal to me for the most part.
I am not very familiar with the old school FFs (NES and SNES) but I have I & II on GBA, III on DS ... I think I still have IV on GBA but I don't think I have VI any more. I can recommend em all but they're far from the top of my list of recommended JRPGs ... or video games for that matter.
So, to answer your question I can really only speak for the PS2 Final Fantasy games and the XIII series, which are a mixed bag.
X is good ... never played X-2. I like the pure turn based battle system rather than the ATB system but each character pretty much only applies to a particular enemy type, so all you have to do is call them up and take out enemies in the optimal order, so basic battles are kinda mindless but boss battles are quite strategic. And the whole game drags on. I've never gotten past the lightning fields. Characters are cool, voice acting is atrocious, setting is unique and the story is pretty imaginative too. If you're a sucker for love stories Tidus and Yuna actually make for a fair to decent one.
XII is very unique. I like that about it. I find none of the characters interesting except Fran and Balthier. Good voice acting. Nice blend of Lord of the Rings and Star Wars aesthetic in a sort of futuristic Arabian setting. Story is your standard stop the evil empire with some sappy character melodrama thrown in. Battle system is pretty sweet. MMO like, ATB with no separate battle screen. Grinding can be fun but it takes place incessantly!! The grind is XII's biggest drag. It gets real old, real fast. License board is the series worst character progression system since it pretty much enables all characters to be completely homogeneous.
I have a very strict love/hate relationship with XIII. Emphasis on the hate. I liked the first one. Was willing to forgive its flaws. XIII-2 is everything its predecessor should have been (which isn't exactly a point in its favor). I really dig the characters. Was really fascinated by the nuances in the relationships between the characters in the first (lots of painful irony). Really liked the survival story. XIII-2 ditches pretty much all the characters and delves into time travel and becomes a mess. Then the story just started jerking me around and that's when I started to lose patience.
XIII's battle system is a mixed bag. Fast, visceral, exciting. Not very strategic and extremely cheap. Tons of one hit kills and reliance on a ton of luck in boss battles.
At first I thought it was a remake of the first game. Wish it was, oh well.
We wish a lot of things out of Final Fantasy games that SquareEnix never delivers on...
Heh... "very crap" doesn't even begin to describe it.
IV? is that the one with that Kain guy? I think I have the GBA re-release.
Oh, I see... well, like I said it didn't hold my interest for very long, so I wouldn't know that. I guess it's safe to say now I might as well just trade the thing in.
Four Heroes wasn't hard either. Hard implies that it played correctly. No, it's just broken and shoddy and sloppy as all hell. I wouldn't wish that pile on my worst enemy.
That's exactly what I told the manager at Gamestop when I returned it. He got a laugh outta that. Sorry, but just thinking about how infuriating that monstrosity is makes my mind boggle. Waste of the plastic it's printed on.
I told him to stay away from 3 because its so freaking difficult. And because of this difficulty, it makes the game boring. 4 heroes of light wasn't that bad, using magic was a pain though.
You thought III was difficult? Really ... Four Heroes is so godawefully bad because it is so impossibly difficult!! It's not even a legitimate challenge. The game just handicaps ya and screws you over with its bland, bare bones combat interface and enemies that one hit kill with every move!! And the game makes you wait turns while enemies wail on ya before you can cast any spells. Enemies don't have that limitation.
No, I stopped playing III because it was boring... but it wasn't hard at all. III is more of FF's standard "spam the attack command" combat. Are you sure you don't have the two mixed up? They're very similar. Except one is boring and the other is the work of satan.