editing code to change layout?

Hi I am currently designing a website http://www.crossrangers.com

There are a few things that i’d like to do with the site but having some coding issues, i wanted to change the background to black, but on doing this there is a white space to the right and left of the content table.

/* Body */
* {margin:0; padding:0;}
body {background:#f4f4f4  url(img/bg.gif) top center repeat-y; color:#000000; font:76% Verdana;}
#wrap {background-color:#ffffff; color:#000000; margin:0 auto; width:760px;}

this is the code i changed – I tried to change the width from 760px to 800 this did remove the white space but the alinment of the page was all messed up

any help on what to do would be great 🙂