Lou Malnati's is VERY good pizza. So good, they have a service where their pizza can be shipped frozen anywhere in the US! Gino's (
www.ginoseast.com) is also great pizza, and another good suggestion would be Pizzeria Uno (
www.pizzeriauno.com).
Onodrim said it: if you're really looking for a high class experience and money is truly no object, Charlie Trotter's is the way to go. But ONLY if you literally mean money is NO object.
I'm a big fan of Phil Stefani's restaurants. I'd recommend either of these three:
Tuscany,
437 Rush, or
Riva.