I would try this, in your httpd.conf file don\'t specify any ip address, just do - Listen 80. So, it will listen to all ip addresses that are available. Then if you can start apache, try accessing with localhost on the server. If you are accessing it from a different machine, first see if you can ping that ip address.
I don\'t know if this will help you, your network configuration is unclear to me. I assume you have a static public IP and you are using private ip for your network using dhcp. you should use a static ip for you apache server.
Hope it helps.
Jake