Thanks! I'd like to do a website using WordPress, and this was my introduction to it....
See > Using WordPress.com to Create a Website http://en.support.wordpress.com/using-wordpress-to-create-a-website/
A WordPress blog can either be structured as a page based website or its conventional post based structure can be retained. That’s why understanding the differences between posts and pages, http://en.support.wordpress.com/post-vs-page/ comprehending the SEO implications of creating a page based structure, and knowing how to use custom menus http://en.support.wordpress.com/menus/
are key to decision making when selecting a theme, and setting up your WordPress.com blog. http://onecoolsitebloggingtips.com/2010/05/12/better-blogging-at-wordpress-com-pages-and-posts/
One one hand, none of the characteristic "blog" features likes categories, tags, authors, dates, etc. can be removed from a free hosted WordPress.com blog without purchasing an annually renewable custom design upgrade and doing the required CSS editing.
One that other hand, one can hack a WordPress.org theme free of charge. Have you read this comparison? WordPress.com and WordPress.org: The Differences http://en.support.wordpress.com/com-vs-org/