Okay what is the best way to set up this network? I would like to keep it as simple as possible. Here are the parameters:

1. I only have one nic available on the server.

2. I only have 4 clients

3. 3 clients connect wireless, one ethernet (it is a combo wireless with 4 ethernet ports)

4. Do not need exchange

5. Do not need ISA

6. Am not planning to use as a web server (just as a file server)

Thanks
Denny

Well, according to your spec's you don't even require a server operating system, just a router.

When you're done, your setup should look as follows:

Internet >> Router >> client PC's (wired & wireless)

I'd say if you only need a file server, forget 2003 server, you will be fine with an XP box where you store all shared files and a couple of printers.
Set up your network as a workgroup, if you don't need Exchange you have no reason to go through the ordeal of setting up a domain and maintaining it.
I'va managed a workgroup of 7 OC's for 4 years now, have just recently upgraded to SBS 2003 and believe me, if you're not very very much into servers, it's a very difficult process.