I've eaten at Tutto Italia, but not at Chefs de France. With that in mind, this is my opinion:
Tutto Italia was good, but nothing special. My guess is that you have an Italian restaurant near your home with food that's about the same quality as Tutto Italia.
Chefs de France is "different," though. Most of us don't have a French restaurant near our homes and, if we do, the price point is higher than we'd be willing to pay on a regular basis. But, you're on vacation at WDW and you're going to be paying higher prices for meals anyway, so it's easier to justify that higher price point since it's about the same as you'd be paying at any other place in the World.
So, my opinion is Chefs de France.