In the learning context, Dreamweaver is not your friend. If you want to learn PHP and MySQL, you can do no better than this book, which has been a permanent part of my professional library since version one.
http://www.sitepoint.com/books/phpmysql4/Get that and work through the examples. There are clear explanations and downloadable code libraries to help you get a site up and running. These are the things you must understand if you're going to be successful using PHP and MySQL in any other context (WordPress, Drupal, Zend, Dreamweaver, etc.)
After you have some grounding in PHP and MySQL, then take on Dreamweaver. It is a useful tool, but if you do not understand the basics of the underlying server-side scripts you will be endlessly confused by the code Dreamweaver generates.
Best regards and best of luck with your project, ~Ray