Screen shots aren't going to help. What you get with the free developer account is just what see with that link. It is free so go ahead and sign up. If you were using an old machine that didn't support the latest Xcode, for example, that would be a good place to download older versions of Xcode. Also included there are some of the oddball things that are not part of Xcode anymore like the Graphics tools and Auxiliary tools. If you want the Dictionary Developer Kit or PackageMaker, you would need a free developer account to access them.
With the paid developer accounts, most of the benefits are behind the scenes as well. You get to install your software on a limited number of devices for testing. You can submit apps to the App Stores. The paid Developer forums don't look much different from these forums. There are some Apple employees around but mostly they just point you in some direction. Most of the help comes from other developers. It isn't as timely as this forum. You may have to wait a week or two for an answer, if any. But there are many more developers there. In my opinion, if you were just starting off, you would get better, more timely beginner help here than there. Plus, your questions are covered under the NDA so you can ask about how to code for Mountain Lion before it is released. I don't participate very much in the paid forums, but I did recently ask a question and get a very good answer on how to do something that Apple had flagged as deprecated but hadn't provided any replacement procedures. Someone else actually knew how to do it. I was impressed.
Aside from the forums, your $99 also gets you a couple of Apple Developer support tickets where Apple engineers will help you with very specific problems. I have never used these at all. For the most part, all of my problems have been caused by my own limitations.
Another place you can look before paying are the Apple Mailing Lists. There are a number of developer-oriented forums and they are still active even with the paid forums. The search feature is awful. Use Google "site:lists.apple.com" instead.