The DMZ option you used was that because the Static Address on its own did not work?
Well the use of DHCP over Static addressing is really a matter of what suits you. For myself I always use static IPs by disabling the DHCP server in the router. However, in my experience I have found that some devices require a DHCP allocated address before you can change it to a static one. (A generic tablet I had was one example). So as my router has no wireless capability I use a wireless access point that only has one address in its range, to allow me to connect this type of device so I can then change them to static.
DHCP certainly has its uses but is (in my opinion) only of use when the Client can register itself in DNS and this is not always supported or allowed. A good example is that of a Wireless Printer. If you install drivers on a PC for a wireless printer there will be an IP associated with it. But if this IP is given to another device then the printer appears not to work and all the jobs go to the print spool, leaving you with a ? over your head as you know it used to work.
I am not saying there is anything wrong with what you have done but by using the DMZ you can't use the same approach for another device, as far as I know you are only allowed one IP address in a DMZ, but am willing to be corrected on that.
As for why there are problems gaming with a DHCP'd address I really can't answer that as we have never been a 'victim' of it, but others reading this may know and post an answer.
