All That Jazz is a nice straightforward choice but I don't think it shows off much about either character.
Somewhere That's Green would be nice because you can show them how you would perform "Ireland." Don't get lost trying to copy Ellen Greene's voice though.
I think "Hold On" is actually a relatively smart choice. It's kind of advice-y like "Ireland" and sounds the most like it of your three choices. And you can belt it if you want.
I'm trying to think of something more comedic. The part of "I Know It's Today" from Shrek that I'm thinking of might be too high. "Donkey Pot Pie" from Shrek would let you have some of the sass (and riffs) from Bend and Snap but there isn't a clear solo part and I don't know how the music is arranged. Is "You'll Never Get Away From Me" from Gypsy too high? I don't know if "Gorgeous" from The Apple Tree is too high for you but you could belt parts of it and it could kind of show how you would play Paulette coming into her own in "Bend and Snap." "As We Stumble Along" from The Drowsy Chaperone would have nothing to do with anything but you could have a lot of fun with it. "What Was A Woman To Do" is probably too high and doesn't have a clear belting section. Is "How Can I Wait" from Paint Your Wagon too high for you? "It's a Perfect Relationship" from Bells Are Ringing? "Someone Woke Up" from Do I Hear a Waltz? The only other song I can think of is "Big, Blonde, and Beautiful" from Hairspray.