I've played the original 2 for the ps2. I feel the first one had a better story line, but they fleshed out the battle system a lot in the second one. I love the fact that while the graphics had a bit of a kiddy feel to them, the whole game didn't come off a childish. I remember seeing the previous for them and thinking - Disney plus Square Soft......doesn't sound very promising.....But I gave it a try because of the Final Fantasy characters in it and was pleasantly surprised.
I haven't played at of the off-shoots for the handhelds tho.
I played them both for the ps2 like chaos, I really enjoyed the story and the key weapons were badass, and mickey was a straight boss. Overall both games were about equal for me, very fun plays, course I haven't played either one since I was about 13 but nevertheless I'd still go back and play em again if I ever got to rummaging through my old ps2 games out of boredom.
I have played the original two as well, and I have played the one for my DS as well. It is abt the same as the other two in my opinion. But others may think different. The only difference is how you level up