OK, if your router has a group of ports labelled LAN, and one separate port labelled WAN or UPLINK or something like that, and you have your other router plugged into the WAN/UPLINK port, try moving it to one of the LAN ports. The concept here would be that you are using the wireless router, but you're not using its actual routing functionality (routing = taking network packets from one network and routing them to another network), just its ability to bridge the local-area wired network to wireless. This is actually the configuration I have my wireless router in, since I have a separate firewall gadget that serves as a wired router.

If your wireless router doesn't have any wired LAN ports, you may be out of luck with the configuration you're looking for, but most of them do have some. (Although it should still be able to come up with a network topology that works for wireless; just with a useless additional routing step.)

(You may also need to configure the wireless router to use an arbitrary static IP address on the WAN port; no traffic will actually go over that since nothing is plugged into it, but the router might complain if it's not configured. 10.0.0.2 might be a good choice for an IP address for that port, since it's a non-routable address in a different range from the one you're using on the local network. If you can just leave it unconfigured, though, that's fine.)