A bright hot room can be cooled down if painted blue or grey providing a calm retreat. Colors will change depending on the time of day or night and under artifical lighting conditions. Look at your colors in these various conditions. Buy a pint of paint and try it out either on the wall or a moveable board if you are considering the same color for a few different areas. This will allow you to easily change your mind before spending a lot of money having the paint store mix gallons of a custom color.
Color is a personal choice.
Yellow , ranging in soft butter to dark gold, will add warmth and brighten a dark room. Red is fiery hot and adds drama. It makes a room glow. Earthtones , from beige to mocha, are warm and restful colors to live with. They also make a great backdrop to easily change accent colors.