For the Net gear DG834G routers:
Static and Dynamic Routing with TCP/IP, VPN pass-through (IPSec, L2TP, PPTP), NAT, UDP, RIP, PPPoE, PPPoA, Classical IP, DNS, DHCP (client & server)
These are protocols the router can handle.
TCP/IP is the common protocol.
The DSL modem will use PPTP or something like that.
NAT is not always needed for some network tasks. S see this:
http://en.wikipedia.org/wiki/Network_address_translationBut you need to read over the documentation and the setup guides provided by Net gear. You need to understand what it means to 'reset' the router/modem. And you have to understand what it means to change the base IP address of either outer itself. At least one of them has to have a different IP for the local network.
ftp://downloads.netgear.com/files/DG834Gv5_SM_31Mar08.pdf
It should not be necessary to use static address on you PCs.
I am willing to help you, but I have limited ability to study long documentation. As for me, just change a few things until I get it to work. When I tie two routers together I cripple the closer one by turning of its DCHP and giving it an IP inside the range the front router or gateway wants for DCHP Doing that I can not use the WAN port. But it works. In effect, the router is like a hub.
To tie two routers using the WAN port you must study the documentation for advanced users. Or just go to the NETGEAR forum and look around.
http://forum1.netgear.com/EDIT: Simple answer. One router will have all its features set in the normal way It is the one that hooks to the internet. Then second will provide connection for additional PCs and will have some things disabled.