Setup NAT/VPN at home? Help me figure out how!?

Dale the short answer is you don't easily set this up. You have to configure the Server to be a router and configure it for NAT. You have to create client accounts and configure the server to be a VPN gateway as well as configure the computers that are going to connect to the server using VPN. It isn't a simple task. You are going to have to do a lot of research on how this technology works and how to apply it to the server. There is a reason why the people who do this sort of stuff for a living get paid to do it.