More information needed. Dark oak? Light oak? You are talking about external or internal paint colours? As a coverall answer, I'd go with a warm colour to complement the oaks yellow heart. Perhaps a mid-toned warm blue, mid to light greens with a hint of yellow, deep terracotta red-browns, these for accents. If we're talking an overall colour for internal walls, you can't beat a pale linen shade with a tint towards green or a lovely rich cream. Naturals are always tasteful and stylish.