Using two routers on a network is rather interesting. After you understand using 2 subnets this all makes since, but in the mean time we are going to just concentrate on just making the setup active with low-end equipment such as a Cable/DSL Broadband Router.

There are multiple types of configurations that you can setup here.
-- We are going to focus on getting the wireless router to Broadcast DHCP, and have the wired router work as a switch. There's a catch: You can use both networks to connect to the internet IF the Wireless Router, and Wired router are configured properly.



Regardless of what kind of routers you are using, there is one thing that will have to be utilized as two concepts/components, and then the link will be made to the internet.

- First: There can only be one DHCP server on a subnet of 255.255.255.0. There may only be one Gateway on a subnet of 255.255.255.0. This is because the subnet of 255.255.255.0 uses all 253 IP's of it's range and may assign them to other devices on that subnet [the IP of the Router, and the Broadcast Address are the other in 2 in the 255 range, the 2 addresses are mandatory to be used for it's existence
-- Technically the IP Scheme of:
{192.168.1.0 would be the network address which is always an Even Number, and the first of the subnet range}
{192.168.1.1 could be used as the gateway, always an Odd Number}
{192.168.1.255 would be the Broadcast Address - the last address of the range}
for the 255.255.255.0 Subnet].

- Second: The router configurations, and the clients. All clients will use the same Gateway in order to access the internet.
---- In other words both networks should be able to connect to the internet. If you need to share data across your networks (PC to PC), I will recommend using the same subnet as the wireless (Which is the one that will have DHCP enabled in this configuration), this will include the same IP Range. The subnets may not talk to each other because they are the same subnet: 255.255.255.0, and in the 255.255.255.0 subnet all of the IP's are utilized for it's IP Range, therefore this is actually a fault in the regard - thus they may not communicate.
--- When you are using both routers, I will recommend to to use the wired router as a switch, and use the Wireless router as the Router/Firewall.

What network you are connected to can determine what computers you may connect to via Windows Shares (CIFS/SMB) for example.

Ultimately: depending on the hardware you are using (what brand - Firmware [EEPROM, Operating System, version] "H4(k3d" or not), you may be able to actually connect to the internet on both subnets, and have the computers talk to each other across subnets; but this is not always the case - like it said, it depends on the equipment, and if you are allowed to create other subnets (vlan's) on your network. Therefore it also depends on the IP Class you are assigned from your ISP; unless you are the ISP.

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Generally speaking all you will need to do is Disable the DHCP server on the wired router, and setup the wired router to use nothing in the regard...
-- You will not use the physical WAN port on the Wired Router, nor will you use the Wired Router for assigning IP's (DHCP).
----- That means DO NOT forget the LAN Settings you have assigned to the router in case you should need to log back into it for some reason or other...



Example: if you have the Wireless Router setup with it's LAN as 192.168.1.x/255.255.255.0, then I would recommend using the IP range 192.168.0.x for the Wired Router.

For the gateway, use 192.168.1.1 (assuming this is the gateway address defined on the Wireless Router [This would also be the Wireless Routers LAN IP Address]).


Wireless Router:
WAN: Setup with the settings provided by your ISP.
LAN Address: 192.168.1.1
Subnet: 255.255.255.0
DHCP: Enabled

Wired Router:
WAN: Setup as DHCP, but do not have anything plugged into the WAN port.
LAN Address: 192.168.0.1
Subnet: 255.255.255.0
DHCP: Disabled


Clients:
DHCP Enabled clients
Wired/Wireless
Should pick an IP from the DHCP offer from the Wireless Router.
Statically Assigned Clients:
*You should be able to assign manually a 192.168.1.x Static IP to the NIC (Network Interface Card).
*You should be able to assign manually a 192.168.0.x Static IP to the NIC (Network Interface Card).


*As I stated, if your clients are connected to both 192.168.0.x, and 192.168.1.x IP ranges will not be able to communicate with each other if they are both on the 255.255.255.0 subnet, but will both be able to connect to the internet.
-- Using both Networks this way may actually be used as a security technique to keep unwanted users off of a private Wired Network (if you wanted this setup) - Whereas the wireless users connected with the DHCP offer (192.168.1.x) will not be able to connect to the Statically assigned IP Addresses unless they are manually given a static IP address in the range of 192.168.0.x.
----- This is included for all services including File, and Print Shares.