Another vote for Lou Mitchell's. They are kind of pricey but they are good.

I have a few others off the top of my head.

Country House - 127th & Cal Sag Road
The Original Pancake House (Several locations)
Eggman - 127th & Pulaski
Izola's - 79th St (We're talking "Down Home" breakfast)
Les Brothers - 87th & Ridgeland
Lumes Pancake House - (Chicago and Palos Heights)

My favorite spot for breakfasts was Gladys' Luncheonette on 45th & Indiana. I think they had gotten closed several years ago for various violations.