Question : How to setup a small business network

We have been having our websites hosted offsite for several years now, however our company has grown much larger and we are wanting to move our websites and email onsite now.  I haven't had to deal with all the technology end of our business before, but I have taken it over now, however, I haven't been this involved with it since back in the Windows NT days and a lot has changed since then.  We have some good hardware and I want to use it all the most efficient way possible and thought I would get suggestions here and hopefully not have to hire an outside company to set this up for me.  My hardware is listed below:

Dell Poweredge 2950 Server -- (2) Dual Core Xeon Processors, 16GB RAM, (4) 1000Mbs ports, (6) 146GB SAS 10k drives

Dell Poweredge 2950 Server -- (2) Quad Core Xeon Processors, 8GB RAM, (4) 1000Mbs ports, (2) 146GB SAS 15k drives

Dell Poweredge 1800 Server -- (2) Xeon Processors, 4GB RAM, (2) 1000Mbs ports, (3) 160GB 7200 SATA drives

(16) Desktop PCs
(3) Laptops -- Wireless Capabilities
48-port Dell PowerConnect 5448 1000Mbs Switch
24-port NetGear JGS524 1000Mbs Switch
Buffalo TeraStation Pro II 2TB NAS
Linksys WRVS400N Wireless Router
Adtran Netvanta 3200 T-1 router
Firebox x55 Edge Firewall
Comcast 16Mbs up/2Mbs down internet
Verizon T-1 service


All 3 servers are running Windows Server 2008 and all desktops/laptops are running XP Pro with the ability to move up to Vista if necessary.

Right now I basically need to know what is the best use for each server.  I need a file server for internal use, print server, virus server (Norton Enterprise software), Exchange server, database server, web server.  We have never been in a domain and I would like to set that up as well, which I figure is needed when hosting our own sites.  So, I guess I need a primary domain controller, and DNS as well.  We've always used the DHCP through the router too, so I don't know if it would be best to use DHCP through a server or keep on like we have been.

If anyone wants to get real ambitious you could point me in the best direction on the best way to setup Server 2008 for all of this as well as I'm sure that will be my next question.  :)

I hate to sound like such a newbie with all this, but I finally have the time to set all this up right and it's just been so long since I was in the IT loop.

Thanks for your help,
Ken

Answer : How to setup a small business network

1.
Microsoft Windows 2008 x64 Edition + Exchange 2007 on the 1st DELL w/16GB RAM
- Secondary DC
- Email Server

2.
Microsoft Windows 2008 x64 Edition + IIS on the 2nd DELL w/8GB RAM
- Primary DC
- Web Server

3.
- Setup replication between the two servers.

The rest is really up to you how you network layout is done...