Leave the ceilings as is. I would paint everything else you consider trim (railings, spindles, etc) white…B.M. Simply White. Walls, a soft green like B.M. Silken Pine, a gorgeous pale green which compliments stained wood.

The ceilings are beautiful. I like Judys suggestions, but I would get the drywall up and paint before you decide what to do, if anything, to your trim. You may want to keep it once the walls are drywall.

Those look like high-quality tongue and groove boards. If you still don't like them after the sheetrock is up, you could always paint them rather than sacrificing them.