Downtown carriage ride at night by Watertower Place is cool, tons of shopping there, Chicago River. A ton of great places to eat my suggestions are http://www.eddebevics.com/ if you love great burgers with a side order of sarcasm. Blue Man Group http://chicagoboxoffice.com/briar-street-theatre-tickets.php , something for every taste so say what you would like to do and we can point you.
If you are going up I65 stop at Fair Oaks Farm at Indiana Rt 10, very cool place.