羅丹 has his own museums, 2 places dedicated only to him.

One of it is Musee Rodin.

Musee D'Orsay is most famous for its impressionism collection - such as Monet, Manet, Renoir, Van Gogh, etc.

However, for the best of Monet, you need to go to a Private museum - Marmottan (near Bois de Bologne Park), that is dedicated to Monet.
Monet's famous Japanese Garden and Water Lilies - in the lowest part of the museum, I do not remember if it is the basement, there is a circular hall. Monet specifically painted the water lilies and the garden "tailor-made" for that hall.

On our last visit (Sept 06) we noticed it had re-arranged many positions where they hang the paintings - the outcome is, it lost a lot of the dramatic effect in the past, but is able to display more paintings. I am not sure it is good or bad. For us, it is bad. For those haven't seen the previous set-up, they wouldn't know and not feel the loss.