I'm auditioning for a Disney singing show and I don't know what to sing.

It depends on you, what you're capable of, what range you have. Sing something you're comfortable singing, that you sing well.

I can sing a little hight but I'm mainly an alto. My voice flows very well

i can sing alittle hight but im mainly an alto. my voice flows very well

Are there songs you've been practicing for a long time, that you're comfortable with?

I'd stick with a song you know well, and sing well. You don't really want to learn a new song right before an audition. It's best to stick with what you already know.

I do wish you luck. I hope you get the job. :)

In most auditions they have some requirements, do they have a written instruction to follow.