If you dont want it to adopt the theme of your Moodle site, simply create the pages you want as a 'mini-site' upload them to your server, or wherever you want to make them available, then add them as a URL to the page/menu wherever you want them on Moodle.
If you want to take on the Moodle theme and navigation, then the Static Pages plugin mentioned is one solution, or simply creating pages as part of the MainMenu block on the front page, hide the block and add the links to the pages in your menus/content as required.