Silman's a very good writer whose books are well written and easy to learn from.
I'd recommend Silman's Complete Endgame Course to anyone who knows the rules of the game and doesn't have a master title - the instruction starts out basic enough for rank beginners, but does get to much higher level stuff later. The layout makes it very easy, though, since you can just read the beginner chapters at the beginning, then come back to the higher level stuff later, as you improve. It really is very well designed to be a long term study course, broken into manageable chunks.
His other books probably should be skipped until you're good enough that major tactical blunders aren't the deciding factor in every one of your games. Until then, you've got higher priorities in your improvement than learning about positional play.
--Fromper