Configuring 2 Wireless Routers To Work Together?

I'm trying to ensure I have wireless coverage in my entire house and having extreme difficulty getting all machines to play nicelyWireless modem router #1 (downstairs in my house) is connected to the ADSL line and has the following config:IP Address = 192.168.1.1 DHCP on DHCP pool 192.168.1.3-192.168.1.100 Subnet = 255.255.255.0 Wifi channel = 1 Wireless router #2 (upstairs) is connected by ethernet cable to Wireless modem router #1 and has the following config:IP Address = 192.168.1.2 DHCP off Subnet = 255.255.255.0 Wifi channel = 11 Different SSID and encryption key to Wireless modem router #1 With this configuration, I can connect to the internet via both routers and all seems to be well. Except... having established a connection through either one, my machines will only make a pretend connection with the other one. By "pretend", I mean that the (Windows) machine says it has an excellent connection to the router but can only see machines on the LAN - it cannot get to the internet even though other machines are connected through the same router to the internet.

For example, if I'm sitting next to the downstairs router and establish a connection with it, all is well. Then I move upstairs and my machine switches to the upstairs router. Signal strength will be reported as "Excellent" and I'll be able to connect to the local NAS or printer but no external devices or sites.I have tried having the same SSID and wireless configuration on both but the result was the same.Today I read the suggestion to enable the DHCP server on the 2nd router but to set it to distribute a different non-overlapping IP range (i.e. router 1 can have a pool of 192.168.1.3-192.168.1.50, and router 2 can have a pool of 192.168.1.51-192.168.1.99)