I have actually found the sevice in Paris to be on par with any city in the U.S. Some people are nice, some are jerks. Most Americans lump the French in one big category, and they most likely do the same to us. Keep an open mind and don't hesitate to talk to people...although I recommend avoiding political discussions in foreign countries
Don't know is theesir has left already, but I would recommend a day trip to Normandy (sobering, but the place breathes history) and Mont St. Michel (abby built on a rock island...sometimes ).
Also, if you head to the Louve, use the underground entrance through the mall. In my experience the line aren't as bad.
Visit Versailles. The gaudiness and richness is dizzying. It gives you a sense of how rich and powerful monarchs were.