Rosemont has a lot to offer too if you don't want to travel far.
A couple really good steak houses in town are Morton's and Gibson's, but be prepared to drop $100 bones for 2 people. Other nice places in town are Giordano's and Carlucci's. You'll be full and still have money in your pocket when you leave.
If you're the gambling type, Rivers Casino is about 1 1/2 mile north of the Hyatt. You can also visit the Fashion Outlet Mall in Rosemont (for the Mrs.) if that is in the schedule.
When traveling to DT Chicago, I'd hop on the Blue Line L train which is a about a 10 minute walk from your hotel. If you prefer to drive DT, be prepared to pay $30-$40 bucks for parking, not to mention the sitting in traffic on I-90 for an hour or more. (see map)
When DT Chicago, there will be all kinds of restaurant's to choose from.
If interested in seeing the city from a boat, take one of the architectural boat cruises. It'll set you back about $33 bucks per person. I took this cruise a few years ago, and the tour guide spoke about the history of the buildings along the Chicago river.
The weather is suppose to be nice this weekend. Have a good time!