Community Server 2.0
Well, after playing around for a while with DotNetNuke 4.0, I switched back to something I know - Community Server. All users and posts are lost - for now.
Only registered users can post. But registering is very simple and fast and only requires a name, password, and email address. Too personal use a@a.com for your email address then. Registering just helps keep the riff raff out.
I look forward to hearing from you all.