I think I'm the only person in the world who tried to visit a trip to Euro Disney and the Louvre into the same day ... and the Louvre lost. My partner went on his own. I believe they have a "speed" tour where you can see the big ticket items (at the Louvre ... actually at Euro Disney, too) such as the Mona Lisa and the Venus De Milo (is that there?). I seem to remember they even have a path painted on the floor so you can get to them , fast. No?
But, perhaps the Louvre is smart and puts their famous stuff in the back, sort of like where supermarkets put the milk, hoping you'll stop along the way to look at a couple things.