Louis wants to become a famous horn player(Similar to the Hook guy), Ray wants to be with his true love(Similar to the guy with the big nose guy), Naveen wants money(Like Flynn), and Tiana wants something meaningful that she's been wanting her whole life(Like Rapunzel)

I can see Mulan and the soldiers singing this. I am sure all the soldiers have their own, private, and inspiring dreams.

^Or simply their dream about girls. I agree with both comments

or snow white and the dwarves

Defentialy Tiana and her friends because it's just so simlar espically to the song When were Human.

that would be funny xD also belle and her friends

Definately fits Tiana and her crew, they all have a specific goal in mind, Mulan and the military guys would be interesting to see too.

can hear Tiana's part going something like this...
"I've got a dream!
I've got a dream!
I just want to own a resturant you see
and with every passing hour
I'd rather be making something like chowder
'cuz way down deep inside I've got a dream!"

"And with every passing hour, I'd rather be making chowder" Haha... That's nice.

and Jasmine & her friends, and maybe Ariel & her friends.

I think it would fit them well.