What is better for user? The site has a lot of text to read and I would like to make it as user friendly as possible.
A light background with dark text is easier on the eyes and your readers will appreciate it on a site with lots of text.
Dark background websites are good for graphic centric sites, such as a photography gallery or something like that. The dark background can show the image colors better.
Also avoid having designs in the background if you can... this could make it more difficult to read as well. If you don't have to have some sort of design or logo under the text try to make the coloring match the background as closely as you can so its just barely visible.