The RPi is my first foray into a Linux environment, so I'm a little out of my depth. I have the Model B and a 1A PSU, an 8GB class 4 mSDHC, a Logitech keyboard and mouse on a Unifying receiver, and a Western Digital 1TB drive. I have a powered 4-port hub as well if I need more peripherals, like a possible WiFi adapter (Ralink RT5370).
My goal is to get familiar with Linux and more specifically Raspbian, and hopefully get a NAS going to share to both my Windows machines as well as three Androids and a Mac. I have flashed the SD card to the 2012-12-16 wheezy available on their site, and completed the basic setup as detailed on their quick-start...and don't know where to go next. I want to get a domain controller going inside my network but may go with a Windows-based DC simply due to familiarity and speed, but if the Pi can do it then I don't have to buy/build a server box.