You can do a variety of things. You can completely overwrite WordPress with a static site, just FTP in, remove all the WordPress files at your domain root and replace them with your Dreamweaver pages. You can delete the WordPress database from your Dreamhost panel. Make sure you get rid of the (possibly hidden) htaccess file, too, or replace it with your own new re-directs.
-- If you seriously want to learn a bit more about web design though, your might want to try figuring out how to customize WordPress themes to look and function like your Dreamweaver design. Learning how to modify WordPress and other similar CMS installs is a valuable skill.