I need help with how to prepare knotty pine walls for painting. My kitchen and dining area have this thick ugly wood all over them and I'd like to brighten the space. The house was built in the 50's but this is the only area with the pine walls.

If you want to paint them a solid color, then priming with a shellac based, stain blocking primer will be the first step after cleaning. TSP substitute is a good inexpensive cleaner for walls with possible grease residue, as is common in kitchens.

They could also be given a white wash look with a semi-transparent stain and clear coat? I'd check with a propaint store for options and the best prep advice and the best paints for the look you want.