The Napoleon Hotel is one block from the Champs Elysees and two blocks from the Arc de Triomphe. It is a wonderful, quiet, first class hotel with wonderful service. I stayed there before boarding the Orient Express to Venice.
I recommend the Hyatt Regency Madeleine. It is very close to the Paris Opera House, Place de la Concorde, Place Vendome, Galleries Lafayette for shopping, and close to several Metro stops. Be warned, it is not cheap, but the rooms are lovely, and you can't beat the location.