Again welcome all to contribute to this post! These are just my opinion based upon my experiences. I am not a professional, but I did train to cook in France, and was an officer in the French food society. That just means, "I am not an expert on wine, but can smell, what I don't like"! Or, as my chef instructor, once said, "Good food deserves Champagne, BAD food DEMANDS it"!
Here are some places you may enjoy, and some I would not recommend;
There is only one thing on the menu here, and you have three choices, rare, medium or well done, but I go on every trip to Paris. Across from the RER station Port Mallot. Nice long walk from the Marriott C-E, not so far from The Ren. AdT. Get there early, they also serve lunch, they don't take reservations. Inexpensive, and great salad and fries, they do bring you comped "Seconds". A popular place for Parisians.
Here's another place that is across the street from the Marriott C-E, that is really good. This is a photo from inside The Alsace, looking on the C-E. Note, the Lamb and halibut as well as the French bread.
Here are a few other places, If you like real sidewalk places, try a place that sits a few blocks away, behind the C-E. Likewise, I think Fouquet's is a "Big deal, not worth it. Other places that are "Big deals" and worth it, Guy Savoy's, La Maree (Seafood), I have posted previous pictures, so will not post them here. Enjoy!