Hi Nick,
Couple methods to accomplish what you'd like. Basically it will depend on what you need/want/have for existing software - and even then you have some "slack" to move with.
Ok, heres the setup I have in the process of completing setup.
Internet access in - I have fractional T1, but if your area can get a sweet dsl (synchronious) you can usually get it cheaper. That goes to your router - and the router can/usually does have some slots to plug RJ-45's into - I have a netopia, not too bad, but there are better - and worse. The Netopia has 8 slots in the back. But I do not use any but 1.
So - internet into Router. Router to Server - 2nd Nic in server going to a hub (I have a dell 24 port hub) and from that out to workstations/clients.
Not only do I have an intranet - but I also host about 7 websites on the server. Plus Email. I needed a microsoft based system because we use mostly ASP technology in our websites.
So for me, the Small Business Server was the answer. It will go up to 50 users. It has included in the package - IIS 5.0, ISA, DNS, Front Page Extensions, There is an exchange package - but I'd recommend Merak - make that HIGHLY recommend Merak. It also has DHCP, Does the ASP Scripting, SQL Server, etc etc etc.
I also went with Norton Corporate edition for anti-virus with 10 clients to begin with (and where I host email - I've found at LEAST 45 virus's in the past week alone).
Having stated all the bells and whistles that SBS has - it is a complex software to learn. So complex that Microsoft even allows 2 free tech support tickets.
If I had to do it again, I would go with Unix, and Apache, along with Merak for email. Apache is free, and theres a ton of modules to make about anything work - even ASP - BUT not all asp will work on it - and forget front page extensions. But it is stable as all can be.
However, SBS allows for some very cool administrative tasks. You can "Push" updates or install some software remotely onto client computers without having to be infront of it. - as long as it's a windows 2000 or xp. And You can naturally set up networked printers. But each printer, workstation, etc use a client license.
If you did go the SBS route, I would highly recommend you find someone who knows it inside and out - and have them completely format the harddrives. And walk you through from bottom to top on how to set it up - this is unless you can afford the time and money to attend a windows server class. I know my way around windows 95, 98, me really good - but 2000 server along with IIS, ISA, etc? it's alot.
If you have not gotten a server - I have had nothing but great experiences with Dell so far. We got the Dell Poweredge 2500, 3 SCSI Raid-5 configuration 18.2gig harddrives - hot swappable, a gig of ram, dual power supplies, redundant fans - 2 1.13gh Pentium III's. SCSI Tape Backup, and a good UPS.
Had windows crash on me once - Dell's support was fantastic - but I also got the software support.
"Insert witty remark here"
Stuart
( Never mind hey?