I just checked the ORD area and looks like there's a Rosemont Theatre, Fashion Outlet and a couple of restaurants just outside the airport. I think that would be a good place to spend the day if I get there early.
So how easy is it to get there? I see the blue line is $5 each way between O'Hare and Rosemont, or is it possible to walk from Terminal 5? How much roughly would the taxi be?
The Rosemont Theatre is for live shows so it won't have anything playing during the day. There is a movie theater across from the fashion outlet mall. Take the blue line to rosemont stop and I'm pretty sure the fashion outlet mall runs a free shuttle to/from that stop, or you could walk it in 15-20min from the Rosemont stop. Don't think you could walk from airport. Taxi from the airport to the fashion mall - maybe $10, I'm guessing.