I recommend you start at the beginning and work your way up. You won't be able to put it down. Then go to the current story hour thread and work your way through it; same deal. Then read the early years thread; that will give you a look at how the party started (so to speak).
Right! You brave man, you. Start on the archived zip file. The first few pages are a little painful, but lord knows it gets better pretty quickly.
When you get done with that, the current story hour picks right up... and that will be archived too, before too long. Then, ifr you've read everything and want a taste of the early life of the campaign, The Early Years is great fun. Phew!