Chicago Medical Area Marriott
We ate at Chez Joel several months ago and thought the food was mediocre. I seem to recall similar comments by other posters. If the OP does not want to eat at one of the Italian restaurants on Taylor, I'd recommend going about 1 mile north to the Market District, where there are plenty of upscale options. Certainly, for French Bistro food, I'd be more inclined to go to La Sardine than Chez Joel.
How upscale are you thinking of?
Taylor Street, two blocks south of your hotel, going east from Ashland, has a number of Italian places. I rarely eat Italian food out, so I'll let others with more recent experience make specific recommendations, but the closest place if you are walking from the Marriott would be Rosebud (a block east of Ashland). But I'm not sure any of the Taylor Street places would count as "upscale" enough.
The closest of the generally recommended upscale places to you would be One Sixty Blue, about 3/4 mile north of you. Search on this board for lots of discussion.
160 North Loomis, Chicago, IL 60607
1500 W Taylor Street, Chicago, IL 60607