Centralizing Pages

[MikeDavison]

Hi,
I have two problems.
1 - I use Dreamweaver 7.
The pages use Placement boxes and a lot of CSS, so I cannot centralize everything to the center of the screen.
I have just finished designing the site. I did this on my PC with a 800 x 600 resolution.
When I load the pages on a Widescreen monitor, at a higher resolution than the pages were designed at, they are all offset to the left.
How can I centralize these pages?
2 - By centralizing theses page I would guess that I will have a border, or margin, at either side of the page. How can I include a background to till up these borders?

[cadenuo]

well 2 things i would suggest one the most used screen res is 1024x768 so just me but i would make your pages with that format first and second you could wrap your pages in a container div and center that on the screen very easy and everything in the container would follow