I like @kelly's idea of picking a lovely fresh color of paint for the door. You can then bring it down onto the stair risers. Either a solid color to match the front door, or go wild and add some decorative elements to the risers with stencils. Or think of staining the door a great color and coordinate the stair railings and risers. I have an idea book put together for just such project that might spark some ideas for you. http://www.houzz.com/ideabooks/16700983/thumbs/Kathryn-Delany-s-Decorative-Stair-Risers

Bronan, if you are over 13 and under 21, then the possibilities are really fun with black wood furniture in a room that could be set up with a ballet barre, or used as a dance practice studio as well as a bedroom! Since the floors are dark, you will need to keep the walls light, Usually in a bedroom you start with the colors in your bedding. If you want a new look, perhaps you could start with a pretty floral like this, paint the wall where you will put the head of your bed a deep coral pink to match the bedding and all the other walls a pale pretty coral too. room a soft, soft pink, and hang soft pink drapery panels http://www.target.com/p/threshold-multi-floral-comforter-set/-/A-14982101#prodSlot=medium_1_13 The coral will pop with your black furniture better / a good one that makes your skin pretty in the light - this one for a headboard wall to test - http://www.sherwin-williams.com/homeowners/color/find-and-explore-colors/paint-colors-by-family/SW6878-animated-coral/ this one for the other 3 walls . . a white with the same coral undertone - http://www.sherwin-williams.com/homeowners/color/find-and-explore-colors/paint-colors-by-family/SW6609-touching-white/ If possible, you might hang drapery rods on the mirror wall, so you can hang (with this bedding) white drapery at both the window and on each end of the mirror - it will make it feel a lot softer in the room if you treat it like a window. You can follow watch for on sale drapery until you can get a lot that is the same. Put the rod at the same height over the mirror as it is over the window. You might paint an inspirational quote at the top of the mirror in the dark coral (using a stencil) so that you visually fill the space between the top of the mirror and the top of the window. You could get a sample size of pale green paint the color of the green in the bedding to paint an extra piece of furniture that you need that isn't quite right. A little desk or vanity, or even a round end table or a bench for the foot of your bed. Hope this looks like an interesting option to you. Later, you can go for graphic black and white bedding and put hot coral pillows on it with the same paint job and curtains and get a whole new look with just new bedding.

I would go with a gold or yellow ... of course I happen to love teal/ turquoise and gold/ yellow together. Something in variations on the photos below... maybe some pink accents if you have a girl or lime green or blue accents if you have a boy.

Alternatively, if you just want to get the water marks out of the wood: Set an iron to warm (not hot) and allow it to heat. Lay a cotton napkin or tee shirt over the water stain. Iron the stain through the cloth for 5-10 seconds, then remove the heat for 20-30 seconds. Repeat as necessary, buffing lightly with the cloth after every 2-3 heat cycles. A hair dryer may used instead of the iron. Set it to medium heat and hold 2-4 inches from the stain. Buff the stain with the napkin or tee shirt as you heat the wood.