You do not mention whether you wooden wall will be painted or stained wood. Either way, there paint products you can use to properly seal and protect the wood either way. You should visit your local paint store and tell them what you are trying to do and see what products they recommend.

If you want to highlight the staircase wall then your could use earthy colours such as a yellow ochre! The wall could be enhanced even more by using suitable frames and making a good collage composition for all the photos that you have (I can see many lying on the dining table). This colour would match well with wooden furnitures

Keep things cool Cooler shades such as grey and blue help walls recede, making the room feel more spacious and light. Bring home the sunshine Light but warm colours such as terracotta or yellow can mimic sunshine and make a space feel bright and airy. Pale ceilings Keep the ceilings in a light colour to make the room appear larger and lighter. While white is your safest bet, you can opt for mint or sage green for a pop of colour.

The reference image wall color looks like Song of Nature 8401 or Pineview 8400 from Asian. Combine this with Nickel Grey 6126 and you should be good to go. Just paint the recess in accent color and the rest in grey. For getting the sense of color in the actual setup, we suggest you get a big swatch done and look at it in daylight and then in the evening with the warm lights on. The look will change substantially in both cases. You will be able to decide better.