I'm not an alto, nor am I any good at giving advice because I feel that whatever song you are most passionate about, that will be the song that you do YOUR best on. But I do advise you to stay clear of Les Mis, Wicked, Beauty and the Beast (for that show) and The Music Man (for that show) 1. because the first 2 are overdone and the directors can easily get bored and have a previously stereotyped reaction and 2. it's not necessarily acceptable / good to do a song from the show you're auditioning for. I'm a Soprano so I can't give Alto advice that well, but good luck!
And the other thing about the Phantom Lady was, Bert, she realized, in the city that never sleeps...
What did she realize, Kitten?
That all the songs she'd listened to, all the love songs, that they were only songs.
What's wrong with that?
Nothing, if you don't believe in them. But she did, you see. She believed in enchanted evenings, and she believed that a small cloud passed overhead and cried down on a flower bed, and she even believed there was breakfast to be had...
Where?
On Pluto. The mysterious, icy wastes of Pluto.