when are you getting the captcha? posting? pms? loggin?
and I've look at the settings and don't see any reason why you're having issues with the PM or updating your profile.. this is odd

as to the board being harder....? It's the most generic layout around.. we've kept it like this specifically for it's "generic" and simplicity.. LOL.
what browser are you using?
I think the problem is we've been around so long the captcha doesn't bother us. Let me see what I can figure out without letting spammers in.