How to improve?

Thanks BadDog. I've tried 10 and they have ALL been available there.

Glad to help guys.

It depends on how you learn - I found books mind numbingly slow as a beginner.    I really liked video lessons on this website as well as Chess.com TV  when they do commentary on games.     

Check out the chess.com study plan:

http://www.chess.com/article/view/study-plan-directory

Seems like a good systematic way to expand your chess knowledge.

Actually since the OP is a diamond member and has access to the ChessMentor, it's probably all he needs.  The Silman courses alone would probably do it. Try this 300 lesson beast if you'd like a challenge:

http://www.chess.com/chessmentor/view_course?id=22

Very nice course, much appreciated.

Don't study openings. Focus on tactics, endgames, and complete master games, especially those annotated with wordy descriptions, not just variations. Once you've got the basics of endgames and some master game study behind you, add in some middle game strategy (Silman's Reassess Your Chess, etc).

I'm smart too. I just barely started playing chess last month and I got up to 1788!