Little Shop audtion song help

I've been struggling to find a song because my voice has a deeper tone to it. And if I try to sing it an octave higher I sound nasily. I don't know if it's because I don't breathe as much as I should or the simple fact that I've been classically trained for four years and have a hard time adjusting.

I find that most Disney songs fit my voice pretty well and I'm thinking of singing either Part of your World (both versions), A Change in Me, or Belle (reprise). And we're also allowed to sing something from the show. Maybe Suddenly Seymour or Somewhere that's Green?