We took the Metro to the Pont Neuf stop just north of the river near the Samaritaine Department store. This was an afternoon ride and there were not too many people on board.
We departed from the dock and headed east and went around the island where Notre Dame is built. After going around to the back side of Notre Dame, then we went over to the west to view some of the famous sights of Paris.
As we traveled down the river, a taped recording described in English and French what we were looking at on either side. The boat was covered so we could be inside where it was warm and dry, but I was also able to go outside to take pictures.
This tour took us past the Musee du Louve, Orsay, and L'Orangery, Jardin des Tuileries, Place de la Concorde, Assemblee Nationale, Hotel des Invalides (Napolean's Tomb), and Tour Eiffel. We went at a leisurely pace and felt very relaxed as we floated down the river. It was a change from the fast paced Metro or walking around the city dodging cars as we crossed the street.
Although this is a "touristy" thing to do, we thought it was very worthwhile and would recommend it as an alternative to other transportation in order to see many sights at one time.