Im currently designing a site and require some help.

I download a template from a website which im using but just wondering whether anyone knew how to do the following.

1. Remove the Three "side bar menus located on the Right Hand Side " and expand the middle section . Everytime i try to do it , it messes up the Webpage layout.

If anyone can explain to me how to go about doing it so that i can do the other pages in the website myself , that would be good.

cheers