Welcome to the Blender Quickstart. If you're here then either you've already downloaded Blender and have no idea where to go next or you just like to read all the documentation before risking putting a virus on your computer (good for you). Blender has many dephs for you to explore and you'll find it's user interface is very well designed, but I know from experence it can be confusing. This page is designed to get you going with Blender, whatever you decide to do with it!
Many of Blender's users are people like you and me who just like to mess with 3D-Graphics. Learning your way around Blender in the beginning can be a pain. The Getting Started Tutorials will be of great help. Particurlarly The Blender User Interface Tutorial and The Blender Windows Tutorial. These will introduce you to the interface and give you a good kickstart. The other tutorials will teach you other basic elements of Blender... it's all a part of the big picture.
After your comfortable with the User Interface you need to go through the whole Tutorial Database and see what you can find. New tutorials are added often. Also, don't forget to check out elYsiun, which has it's own tutorials and a message board for asking general Blender Questions.
If you want to help out with Blender Development you should check out the Development Section in the InfoCenter which has some useful articles as far as how to go about helping in the development process. You should also start hanging around Blender.org which is basically dev-central for Blender, it has it's own message boards to talk on and various other things to do and see. You might also want to subscribe to the mailing list. More information is avalible in the InfoCenter.
What're you still waiting around here for? I gave you plenty of links! Get started exploring Blender, and most of all have fun and be creative!