Pikmin: I adore how the Pikmin sound! They're already cute, but they'll start singing as they're following the captains around. But if you happen to leave one behind, it'll give such a sad disappointed yawn. sad
Okami: Man, this game is chock full of lovely details. I'll mention two. One is how Ammy tends to fall asleep when someone's given a large amount of exposition. The other is how grass and flowers spring up behind her when she runs! Only they're withered in areas of strong evil power.
Darkstone: This is a Diablo clone that's not that bad but not that good either (I never got the chance to play Diablo itself). But there's one point...
when some townspeople turn to stone, the chicken running around town turns to stone too!
Dark Cloud 2: I like the amount of detail that went into houses and buildings. Like you go in a bar in the first town and it's decorated with a car! Or there's a house with many pumpkins, which belongs to a shopkeeper who has a pumpkin holding his shop sign (as well as a giant watermelon in the store).
LoZ: Wind Waker: Zelda games tend to have many interesting details. So I'll just mention one: the way the grass reacts to the movements of the winds. It's such a nice touch, giving extra atmosphere.