One of the smartest ways to add warmth and comfort to a plain looking room is by adding molding. Crown molding runs along the top of the top of the wall and intersects with your ceiling. There are many different styles to choose from depending on your desired effect. You can also add a chair rail and wainscoting which will give your room an even more traditional look as well as protect your wall from nicks and scrapes. And the final piece of railing to install is the baseboard molding which will finish the look.
Your local hardware center will have the supplies you need to do this yourself and it does take time and patience as well as a little know-how with a table saw. There are pre-made molding kits which make the process easier but they do cost more.
>Selecting Molding [Lowes]