The economy/"Standard" bedroom with two small couches facing each other over a small cafe booth-like table. At night the table and sofas fold down to make a bunk AND a fold down bunk from the top comes down (getting up there can be rather exciting...)
Going through or to Washington, DC or Chicago? Be sure to plan some time just to explore the Union Train Station you'll stop at in each city. Both of these stations have been recently renovated and give a hint of the grandeur of the golden age of train travel.
If you have an option, try not to sit too close to the front end of the car. The view will be better a little further back, particularly out the side opposite your seat. This also applies to seats opposite and just behind the center stairwell area on Superliners
Be careful your camera's auto focus doesn't focus on the window instead of the scene outside and try to avoid glare. See Photography Tips
Take a lumbar pillow if you have lower back problems, like most public transportation, the seats have very little lower back support for long rides.