I assume you've done research in books or online, so just a few comments:
As a rule, dine where there's lots of people.
Be extremely alert at the Louvre Metro stop, including in the Metro itself, which is a major place for pickpockets.
No need to stay in one spot near your hotel. Get around on the Metro system, it's not complicated. Go see Notre Dame and its amazing rose windows. You might wander in to hear a choir rehearsing.
Museum wise, the major guidebooks are accurate. If you like Impressionism and post-Impressionism don't miss Musee D'Orsay. If you like modern and avant garde don't miss the Pompidou Center, which has a bonus of having an amazing city view at the top floor.
Be a building watcher: Enjoy the incredible Art Nouveau facades and ironwork.
Get some bread and cheese (and meat if you like) in the little shops and make a meal outdoors, weather permitting.
Enjoy!