I am trying to help a friend out who has a small home network in 2 buildings with 2 wireless routers. He has fiber from the building where the dsl comes into, running up to his house where a second wireless modem is. Both are broadcasting DHCP but I only want one of them to do this. Ultimately I want his server(2008) to broadcast DHCP, but just one of the modems is fine for now...any recommendations? Thanks!
Leave one DHCP server on, let's say the one in the router where the DSL connects. Turn off DHCP in the second router, also use same SSID, but different radio channels from the primary router that has DHCP on, that will turn the second router into an access point. Also you should assign the second router a static IP address in the network range that is outside the the DHCP assignable range. Use only one network to do all of this, for example 192.168.1.1 for the gateway/DHCP router, 192.168.1.129 for the router used as AP, and allow the DHCP assignment range of 192.168.1.2 to .128
To modify the second router it is necessary to connect to it, type in its current ip address into browser and open the configuration pages for the router.