Cafe Ba-Ba-Ree-Ba. it's in Lincoln Park - Halstead & Armitage. It's my favorite place in the city. I LOVE their bacon wrapped dates. And they have fabulous sangria.
I also LOVE Italian Village - that's in the loop. I forget where exactly.... Adams & State maybe? It's definitely more quiet.
Also - Captial Grille. It's pricey, but I've eaten there in nice jeans and a sweater with boots - that kind of outfit. It's like Erie, east of Michigan - by Northwestern.
Devon - is a FANTASTIC seafood restaurant. Also slower paced and quiet. a bit on the upscale side, not sure about price you're looking for. It's Chicago and ...... Rush? or maybe State. That would be walking distance to 4 seasons, I think.
That's all I can think of now...... If I think of more, I'll update.