Read More disabled but content div width too small

Hello! My question is maybe a simple one, but I can't understand so I need your help! I've disabled the "read more" link which appears on the left of the body of any basic content node, but now the body appears all stretched...how can I increase its width?using firebug I've already tried changing content width... and set padding and margin to zero but nothing!!!!
another question is where do I look to take control of background images? if I want a full image to display as background, i.e., and not a repeated pattern?
I know maybe I'm asking trivial questions, but really any help could save me tons of workarounds!!!

Thanks to everybody