If anyone can tell me the software used to create the walkthroughs on the website I'll actually go ahead and create a full walkthrough.
Currently I have pfSense running with RADIUS. The RADIUS is checked against AD using an auth server that is not a domain controller but a domain member. This is so it'll work so long as any DC remains functional (5 total). The auth is done in Server 2008 (maybe moving to 2008 R2 soon).
Captive Portal is using https. Wireshark verifies that we can't pick up any sensitive information from logging in.
Filesharing is blocked using a combo of the traffic shaping along with OpenDNS.
In the event of legal issues, logs include username, IP assigned, MAC, times, and all the essentials, stored in a RAID 5.
The setup we're using now is pretty much tailor-made for large-scale wireless deployments, especially at educational institutions.
As I said, I'll create a walk-through if I can get clarification on how to go about doing it best.