Wireless authentication

I know there are a handful of ways to set up wireless authentication. Some better than others. We have a customer oriented wireless network and we are trying to build a central authentication system for it, so that we can add and easily control customer radios from one location. What types of authentication should we be using? What should be avoided? Any experiences to share? Additionally, would we be able to route traffic to a captive page if the customer is placed on hold or doesn't have an account yet? I suppose that more of a microtik list question, but I'm just asking in case anyone knows. Thanks, Dan Johansson