There is only one main page for posts in a blog and all posts will display on the main blog page. There is no way to exclude posts from the main posts (blog) page. The front page of the blog by default will display your posts (not pages) in reverse chronological order, with the most recently published post on top. Though there is only one dynamic page in a blog for posts and we cannot post to more than that one page, we can create the appearance that we have posted to more than one page.
Please see the entries that follow:
Creating a custom menu http://en.support.wordpress.com/menus/#creating-a-custom-menu
Adding static pages to a custom menu. They are not category pages and they do not automatically update. http://en.support.wordpress.com/menus/#adding-pages
Adding the dynamic automatically updating Categories pages that the software creates to a custom menu
Here’s a link to a custom menu walk-through > http://onecoolsitebloggingtips.com/2011/08/11/wordpress-com-custom-menu-walk-through/
There are many common errors, misunderstandings and misconceptions when creating custom menus and you can read about them here > http://wpbtips.wordpress.com/2011/12/19/custom-menus/