Building a Windows client/server network

We plan to build our own client/server network composed of Windows 2000 File Server, Exchange Server and Firewall Server. Can you direct me to documentation on the pros and cons of keeping these as separate servers vs. running Exchange on File Server and running the firewall on Exchange Server?

We plan to connect 25 users in one location with 50 users in our main location. Internet access would be controlled through the main location. We also hope to add a Citrix Server or two and need to know if there is a cost-effective alternative that provides the authentication/security that Citrix does, keeping in mind we will be linking two locations using a VPN solution with mobile users. Is New Moon’s iQ2 better than Windows Terminal Services and/or third-party terminal emulation software?

In reverse order, Dave Kearns discusses iQ2 in his Network World Fusion Windows Networking Newsletter and provides a link to the free “Definitive Guide to Windows Terminal Services.”

To find documentation on the pros and cons of server separation and guidelines for Windows 200X network planning, check Microsoft Technet, the System and Network Security Reading Room and the Windows 2003 deployment resource kit materials.