BM has a caulk for that purpose. Use the best caulk. Wait 24 hours before painting over the caulk. DAP Dynaflex 230 is also a good choice. Examine the chair rail with your finger tips. Smooth out any rough areas or dust nibs. Nail holes should be filled with wood filler or heavy spackling. Sand smooth when dry and spot prime before painting. Never use caulk in nail holes. Note: Fill nail holes, sand chair rail smooth, then caulk after clean up. Michael

whats it made of? wallboard should be flat or eggshell at most. wood can be semi gloss or same as your trim.

I'd replace the carpet before I painted that paneling. In these pics, it looks good and adds a lot of warmth to the space. If it's really well done and good quality, I'd think twice about painting it. Also, painting walls white does not necessarily brighten a room that doesn't naturally get a lot of light.

I don't have a good picture of that space but I do have a good image of a north facing bedroom where I have Ballet White on walls & ceiling. In this one image you can see all the various undertones that pop out with this color depending on how the light hits it. It's a real chameleon! All the wood work here is Shaker Beige. At the top of the picture note the ceiling is angled and there you can see how Ballet White has a pinky grey tone. On the wall above the shoes it reads much brighter - a grey/taupey white. It is absolutely a 'muddy' color, not 'clean.' I have used it successfully with challenging hard surfaces that I can't change right now (like this orange pine floor, where I have a pinky-taupe faux travertine in a laundry room, and in a guest bathroom with a pinky grey granite countertop). If you don't have a reason to use it, I wouldn't just because it is so variable. IMHO White Dove or Simply White are way better colors and far more consistent across seasons and surfaces. I would paint some large samples and move them around the room. Good luck!