I believe you can get a free developer account with Dreamspark, but I'm not sure if you got one already or not
No real benefits of having one until you develop your first Windows Phone application. The developer accounts' purpose is for publishing apps, really. A little documentation here and there but not really helpful. I think if you are starting from scratch, the best place to start is from learning C# from scratch. Just search up tutorials on the internet, they really help! Tutorials everywhere on the web, ranging from Hello World to LINQ, Strings to Threading.
I've been programming for quite a while now, and it's been a great experience so far, you won't regret it! The way I've started was from programming books (Visual C# 2010 Step by Step, for example). I didn't read all the details as some were hard to comprehend at that time, but I read over most concepts and paved my road. After that, tutorials on the web and YouTube should help as well. After you get started with developing your first app, if you run into any troubles ask StackOverflow. They're great! (just don't ask beginner questions at the site, as they downvote those kind of questions).
I've started programming at 5th grade, learning Visual Basic. After I got pretty good with it, I moved over to C#. So, if you feel overwhelmed with C# at first and if you're sure you think you need to start with the
basics (no pun intended) and build your foundation, go for it.
Also, feel free to PM me if you have any questions!