Castles near Paris - Versailles, Fontainebleau, Pierrefonds, Chantilly, Vaux-le-Vicomte, Compiègne among others.

Hi Rajesh
If seeing the Champs Elysee is on your 'must see' list (as it was on mine on my first trip to Paris), then I suggest you take the Metro to one of the stops part-way along the Champs and walk up to the Arc de Triomphe.
The Champs ELysee definitely falls into the category of a grand street - well worth walking a short length, but to do the whole length may take too large a chunk of your short time in Paris.
As well as seeing the Tomb of the Unknown Soldier at its base, you can go to the top of the Arc; the views from here are excellent, and you'll be fascinated to see the 5 lanes of traffic swirling around the base of the Arc. Cars seem to dodge each other changing lanes - I'm amazed that there aren't more collisions! Di