Greek Town and Wabash Avenue both require walking quite a bit out of your way (a good half mile each way to the west and east, respectively). There are a few closer options.
Avec is not far from the Ogilvie Center. Its size (small) and reservations policy (none) make it a bit of a crapshoot in that you might wait a while to be seated, but later on a Sunday, I doubt it would be much of a problem. Open late seven days a week.
For delicious Chicago-style deep-dish pizza (and my personal favorite),
Giordano's has locations near the train stations - at 223 W. Jackson near Union Station, and at 310 W. Randolph near the Ogilvie Center. I'm not sure about the Jackson location, but Metromix says the Randolph location is open late on Sundays. Call ahead from the train with your pizza order to avoid waiting 30-45 minutes while seated for your pizza to bake.