Looking to come see Chicago for our 1st time. Tell me where to go, what to see, what to do?

Going to see one of these games; haven't decided which one and don't know squat about baseball (any SOS hook up for 4 tickets?):

Cubs & Oakland A's Thursday 1:20PM or Cubs & LA Angels Friday 1:20PM

Navy Pier

Double decker bus tour and/or boat tour

Some mobster stuff would be cool

Could careless about art, water fountains or tall buildings.

Affinia Chicago a decent hotel?