OP,

First, do you like the blue? Or do you want to start from scratch?

A couple of ideas regardless of your paint choice, you can break up horizontal wall space using frames, like the way framing is used to break up tall foyers, e.g.,:



Alternatively, you can use furniture to create separate spaces, e.g.,:


You definitely need to anchor anything like a bookcase so it's not a tipping hazard.

Paint color isn't the only thing you need to rely on:
http://www.apartmenttherapy.com/dividing-space-without-building-walls-clever-furniture-placement-and-more-206434

Need some suggestions. Our house is a ranch style with kitchen, dining room, living room and bedrooms on the same floor. It's very basic.
Imagine a rectangle with the dining room on the right and the living room on the opposite side. No furniture or panels divides these two rooms. Top part of the rectangle in the living room has a rectangular window about 4x6 feet big. On the same wall in the dining room, there is a sliding door. From the main door foyer, you can see the boring living room. And from the living room, you can see he boring dining room.
The largest dining room wall is painted in a solid blue. Kinda like this blue on this website.

Furniture:
Dining Room - Walnut color antique dining room set. There is a hanging chandelier. A mirror with black frames on the blue wall.
Living room - a darker then walnut antique grandfather like clock in the corner and a red bright red sofa against the wall. There are 2 old Ikea leather poang chairs.

What color would look good on the living room walls? The big blank wall is on the opposite side of the blue wall in the dining room. I don't mind adding colors but it seem to lack in patterns. And the dining room and living room seem rather dim.
Any ideas?

Thanks