Which is the BEST Disney Princess Song in general?

"Part of that world", definitely. In addition to great music and lyrics, this song is also about wanting changes and most importantly - wanting to MAKE a change. The theme of the song was already defined by Ariel's line she said prior to it: "I just don't see things the way he does. I don't see how the world that makes such wonderful things could be bad". Ariel can't judge the human world because for as long as she had been exploring it she never saw any proof of it being a cruel, barbaric or awful place as her father painted it to be. Instead she saw creativity and beauty that she got drawn to. And she wanted to be a part of it because she felt like it's a place for her, a place she belonged to and I think it's a very relatable song for young people especially, since many of them struggle with wanting to move out and live in a different place and at the same time desperatelly wanting their parents approval and not getting it. It's the song that defines a feeling that comes before you make some significant change or an ultimate choice.

Part of your world and reprise

Almost there. To me it has the most important meaning, instead of wanting to marry a prince at first she wants to start a career, all for her father! Isn't that so sweet? After all those years, through everything she had to deal with she didn't give up. Even after some racist people who wouldn't allow it she didn't give up. And this has nothing to do with the song but in the end sue got her prince AND her restaurant. This song relates more to reality than the other DP Movies.