I'm having trouble figuring out what you are asking, Is this what you meant to ask?
If I have interpreted your question correctly then that means you have a blog at something.wordpress.com. My next guess would be that you either came to dreamhost because you wanted to change the URL to YOURBLOG.COM or you wanted to customize some aspect further than you are allowed to at wordpress.com, or both.
If all your looking for is the vanity URL and you have registered the name here, there is a way that you can simply change the nameservers for that domain to wordpress.com. Once that's complete, your still hosting the blog over at wordpress.com but you have a vanity URL.
If you are wanting to customize and host your entire installation here, then you are on the right track with the one click install.
I'm afraid beyond that one click install, "dreamhost" doesn't really "help" you learn, or get you started on your project. Dreamhost just provides domain name registration services and web hosting if either or both are what you need.
I'm afraid we can't help much until we know better what you are trying to do, or thinking. If I have missed guessed about your question, or made wrong assumptions, then you will have to tell us more, because although we are helpful we really aren't mind readers.