I wouldn't paint your built-ins. And I especially would not paint cream above your mantle. All that will accomplish is placing the focus on you TV. For the built-ins, you could do a light solid or faintly patterned wallpaper. That will lighten the built-ins and bring in some interest.. Is there another place in your room for your TV? If so, I would move it and hang a large piece of art or a collection of pictures.

I'd paint the backs of the bookshelves White Dove if you want to brighten things up. Maybe get some better lighting instead of the 'spot lights' type. doing the backs of the builtins will look better than partially painting around it. All of that wood trim and panel are woven in to each other, so it would be hard to just paint one portion of it.

Hard to find one, but use your imagination w/this picture.

In fact, I like the look of this room. could be similar to yours .

I'd do a diff wall color, like this white, and trade in the red blinds for something lighter. I'd switch the yellow walls to a nice white like this^, and trade in the red blinds for something like this

this is similar to yours if you painted it all white. (minus the crown).

I also found this to give you an idea of how a paint color would work w/the wood crown.

No...there is nowhere else for the TV to go. What about spitting behind the TV same color as walls? The family room flows from the kitchen

I see why it's dark. the spot lights do nothing. the dark golden wheat wall color, along w/the dark wood, really suck up what little light there is.

I still say paint the walls White Dove or Simply White, and try the other blinds like I posted, above.

I'd switch out the ceiling fan (get a floor fan) for a flush mount like w/at least 3 bulbs

Do you know if there is drywall behind the wood panel behind the TV? If so, you could possibly paint the wall the same color as the rest of the room like you asked. If none of these suggestions is possible and you want to paint the panel behind the TV, then go for it. Remember once you paint it there is no going back. Another suggestion, would be to tape some light colored paper on the wood and see how you feel about it before you decide to paint. I just hate to see you do something that you can't reverse is you don't like it.

Half the trim in that room is already white. I'd go ahead and paint the crown molding and built-ins (to include the fireplace wood) the same white as your trim. You can leave the back of the built-ins the natural wood to add some contrast.