Oh boy, there's a couple of good points in here but so much that is wrong.

Off to bat, don't edit iptables manually anymore. Use ufw.

I just setup a new Ubuntu server (12.10) this weekend and while I'm still tweaking it, I've been documenting my process.

I'll make it available here: https://docs.google.com/document/d/1J2o6Lmq00Lk3k3HPUVKnOvSK...