I have played KH I and II, and I freakin' loved 'em. Probably one of my most favorite games ever.
I liked the combat, even though it was a button-masher, in the sense that you only use one button to attack, the characters (FF, Disney and the game's own) are memorable, they're all great characters.
The story is amazing, the games are long.
And I've seen so many people that don't want anything to do with it because it's Disney, but they're fools.
I ignored that, played the game, and loved it.
Kingdom Hearts 358/2 Days is my most anticipate game on the DS, and Birth By Sleep is the most anticipated game on PSP.