Linux solutions for radius or captive portal

Hi,
I would like to protect my home wifi network by using a captive portal or a
radius server to enable WPA on my access point. Any hint? What is the easier
software to use? Any Linux distribution that has already installed a radius
server or a captive portal?
I found zeroshell at http://www.zeroshell.net/eng/download that is a livecd
with radius and captive portal already
integrated but I think It's too complex for me.
Bye
Peter Elen