I only know Paris, but really the only thing I can tell you is to look for places off the beaten path (not so easy in Paris) with French-only menus. That means stay the fuck away from Champs Elysee and the area around the Eiffel Tower. Zen near the Opera (the old one) is great Japanese food that won't cost you a ton of money. That's the only restaurant name that I can remember. Every other great meal I had in Paris was just in little corner restaurants away from bigger tourist attractions.
The main street that leads up Montemartre from the Place de Clichy has a wine shop (to buy your own bottles), a butcher, patisserie, vegetable stand and cheese shop all on the same block. Every store is exceptional and that'd be a great place to put together your own lunch. It's easily accessible from the 13 line (the 13 north of Place de Clichy is a fucking nightmare though so don't miss the stop). If there's something you'd still want to pick up that isn't available on that street then head back down the hill to Place de Clichy and head south for a block until you see a directional sign that says "Stalingrad." Walk another block down that street and there's a "supermarket" (like 5 aisles) that has whatever else you'd need.
Sorry that I can't be more specific with street names, but it's been awhile.
For wine just ask the waiter for recommendations. They're all fucking experts there.