I'd stay away from the city.
Fly into O'hare and Stay in Rosemont right next to the airport. Take the Blue Line to the Red Line transfer to get to the ballpark.
Great restaurants in Rosemont (Gibson's, Carmine's, Harry Caray, Morton's, Capital Grille , Giordanos (if you crave Chicago deep dish)). You also have our best Casino there in the area.