If you are a designer and want to explore web development, make no mistake thinking that learning Dreamweaver will make you a web programmer. Please don’t take this harsh, anyone is capable of learning how to program a web page, but I would recommend taking the “following approach” in becoming a proficient web developer.
Dreamweaver is simply a tool ( not a good one in my opinion ) to help you code a web page. However, if you don’t understand what is going on, then your page-source will end up like those ugly brochures with bad typography and full of photoshop effects. In the beginning, it’s perfectly fine to stick with plain simple valid HTML page, there is nothing wrong with that… stick with two column grid Helvetica and you’ll be fine.