Hi adam,
I think i know you in real life- do you go to the e2e4 tournaments.
as for the membership- tactics trainer is good. try doing plenty of tactics. unfortunately you cannot use chess mentor as paulgottlieb suggested as you only have platinum membership. (although there are a few demo chess mentor lessons you can do)
the full list of features is at http://www.chess.com/membership.html
is chess.com good at inproving ur game im about a 150 at the moment(1735)and ive just bought a platnum membership