Yes, in that case you would want to use the WAN port on the second router, it would be configured as getting it's IP schema through DHCP from the first router, and you would want to turn back on DHCP but configure the LAN side to a different subnet, say something like, 192.168.2.1 for the router address and 192.168.2.2 through 192.168.2.254 for DHCP allocations. On the wireless side of the second router, you'd probably want to use a different SSID, maybe even a different channel.
I have that same setup in my house SSID's are WE and WE2 and channel 9 on my primary and 6 on my secondary, both use the same security encryption and passphrase. Works fine. No issues.
Regards
Randy