CSS/XHTML help for a website, scaling and centralizing

I need quickly help with fixing the CSS layout for my website. The CSS is already provided but I want you to make it perfect! Please start looking at it here: [login to view URL] What is important that the entire design is centralbased, that means in the middle (left and right) and middle (top and bottom). The top, bottom, left and right should be in white color. The person I hired can not fix this issue with CSS. Another thing that I want is this website to keep same scaling in all resolutions in all web-browsers. So I want the entire website with its main content, including the shaded background image to always stay in middle with white space above and below the image, and not just on the sides. I hope that this is a good explanation to how I really want this to look like. I am attaching a photo of how I would like the website to look in all resolutions. This should be a very simple task for someone with CSS experience.