Using imac 10.6.5 as router (with WiFi as the WAN)

Question

Happy Holidays,
I have a few questions before I go out and spend the money on an Airport extreme. I have not been able to find much information on the specific setup I have in mind.
Background: I have an iMac that connects to the internet through Optimum WiFi via the internal airport interface. I would like to bridge that internet connection to the wired ethernet port, with a wireless access point attached to it for a few devices in my house (iphone/xbox/etc...).
Questions:
1) Will the iMac act as a DHCP server on the ethernet port to give addresses to clients?
2) Can I connect an Airport Extreme and my iMac through ethernet (I am assuming I will not use the WAN port) and use it as a normal access point? (As to not do any NATting/DHCP itself as it would if it were the router).
Basically I want to bridge 2 WiFi networks (1 WAN, 1 internal, connected through the ethernet interface) for internet sharing and access between the devices. I like the Airport Extreme because it has wired ports as well as AirDisk but all of the setup scenarios I have seen so far describe setting it up either as a Router or Wireless extender.
I "could" just connect all of my devices to Optimum WiFi, but I would like a fast internal network for the remote apps I use on my iphone, streaming, as well as any wired devices.
Thank you,
Jack
1)

Answer 1

Thanks for the reply.
I am currently set up in an apartment by work for 6 months. We have Optimum Online at work, and with that comes the use of Optimum Wifi. So I do not have a router at the apartment (am trying to avoid purchasing separate broadband service that will only be for a few months.)
- My iMac connects directly to Optimum WiFi, which has a strong signal in my area.
- If I use internet sharing FROM my Airport (on mac) TO ethernet, that should be the only NAT. The iMac would act as the DHCP server, and the airport would simply be a wireless access point and a switch. (With added support for AirDisk, etc)
- I've set up similar configs easily with a number of wireless APs (From SMC, Netgear, etc...). My main question is if the Airport Extreme can work just like a normal AP would, without all the DHCP management.
I could just pick up a regular AP like http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=44682 40&CatId=372 and be done with it. But I like the extra features that the Airport Extreme has, and I will eventually use it as a router once I have a permanent apartment and proper broadband.
Opt Wifi --> Mac Airport -> Mac (w/sharing) -> Mac Ethernet -> LAN port on Airport Express.
My hope is clients connecting to the Express, should be getting the IP from the iMac, just like a plain Wireless AP would work.
Thanks again.