Hobbies & Interests / Interior Design/Decorating

Our dining room is rather "blah" and DW wants to do something to spruce
it up a bit.  New curtains and paint are being picked, but the subject
of a chair rail has also come up.

The room itself is off the entrance foyer and very easily visible
through a large wide arch about the size of a pair of french doors.
If chair rail were to be put in - and this is where I come in - where
should it stop relative to the arch and window?

Shape of the room:
====WINDOW====
|             |
|             |
|             |
|             |  
|             |
|             |
|             K 
|             |
|            =
==TO FOYER =|

K is a door to the kitchen area; TO FOYER is the arch

There's about 2.5 ft of wall on either side of the window.           

The wall between the K door and TO FOYER is a bit odd so let me 
describe it a bit.  There is about 8" of the K wall below the "K",
then there's about a three-foot jog towards TO FOYER, then about a
one-foot jog towards TO FOYER.

Here's the kind of arch we have on the TO FOYER wall:
http://3.bp.blogspot.com/_mfTS8xinPHk/TJF1WLurCBI/AAAAAAAAAS...

Where should the chair rail stop relative to the arch?

If I did wainscotting on the lower part of the walls, would I do the
two long walls and the window wall, but skip doing anything on the
portions of the wall near the arch?

Any other ideas for dressing up the room with some detail? It already
has crown & base molding.

BG