Orange brown checker board type background does not go with a blue white table set up for a forum board or any table structure for that matter. I suggest shrinking your header logo image down to small, or whatever that image means. Also that is a default mybb table style, here ill give you a link to some cool mybb styles. http://www.awesomestyles.com/mybb-themes . Check them out and maybe you will find a theme you really like.