I agree wih Ixian on the HTML front. Also, while I am not up with the new Dreamweaver versions, it didn’t used to create good code for SEO aside from which it used to put in a load of superfluous code that mafe it difficult to learn from and edit manually. Or simply put, you can outgrow it.
I use WordPress a lot although I’ve heard good things about Joomla and I’m in the process of installing a version. I heard WordPress is easier for newbies and I can vouch for it’s SEO capabilities when you explore the plugin side. Very versatile.