Often people answer networking questions and totally confuse the asker by not explaining, so I will try to illustrate very clearly.
You have your webserver local address 192.168.1.100. This is only accessible by machines on your local subnet.
You have your global address 188.8.131.52. 184.108.40.206 routes to your router from anywhere on the internet.
Without DMZ or any ports forwarded, all incoming connections to 220.127.116.11 are dropped by your router's firewall.
Right now, on your LAN when you trying to access 18.104.22.168, it works fine, right?
Go into your router configuration, forward port 80 to 192.168.1.100.
Turn off DMZ completely.
You should now be able to access http://22.214.171.124
and it should be your webpage, assuming you don't have any sort of firewall setup on your server.
Oh and leave the ports.conf as Listen 80.