As 'tarded as Chicago is, it is a fun place to visit. I recommend taking CTA trains and busses everywhere you go. It's fun to be like the locals. Genos is good stuff. Navy Pier is a little overrated IMHO. The science and industry museum is cool. Unfortunately I had to catch a flight so I didn't get to stay long the day I went. One of my previous employers was based in Chicago so I had to make a few trips up there.
Unfortunately the training center is in Mundelein, so we're having to rent a car to get to and from the city but we'll probably do the trains when we get into the city proper. Depends on what parking is like, if it's anything like NOLA then yeah park the car and ride the trains and buses. The train in from Mundelein takes 2 hours and with our short stay time we don't want to waste too much of it.