ow_sidebar{

//add this line

display: none;

}

then you will need to edit the left margin of 

ow_page_container, something like that to align it to center: 

.ow_page_container {    width: 1000px;    margin: 0px 0px 0px 196px;    }

also you can play with the width of ow_canvas and ow_menu_wrap