Network Re-Design Needed

Current Network Setup:
I have Cox Business Service broadband with a Static IP Address and no ports blocked. I currently have a cable/DSL router (GW IP: 192.168.1.1) hooked up to the cable modem. I have 2 servers behind the Linksys Wireless router: Server 1 – RedHat 7.3 IP: 192.168.1.101 This is currently offline. It is a DNS, E-Mail, DHCP server. Server 2 – MS Windows 2003 STD Server with Active Directory IP: 192.168.1.102 This is currently online. It is a Active Directory, DNS, DHCP, IIS 6. Server 2 was never online when I had Server 1 online to prevent conflicts between the two servers not being configured to act as 1 network (if that makes sense).
Overall Goal:
What I want to accomplish is to remove the Linksys as my router and install a server to act as Firewall and DNS (external I believe). This can be either a RedHat 9 or MS Windows 2003 STD Server. I am not sure which path to go because either way I want to configure Active Directory for my Windows clients behind the firewall. The second server will act as AD Controller, internal DNS, E-Mail, DHCP, Web.
Am I thinking about this the right way? I need some help on how to setup my network making it secure, I would like to remote access into my W2K3 server using Remoter Desktop Web Connection.
I’m looking for some ideas on what you think a good way to redesign my network would be.
Below is a basic picture of my current setup, it’s not great, just something I put together in about 10 min.


I would appreciate any input and advice that anyone could give me. I’m really trying to come up with a good setup and learn in the process. Thanks in advance.

-Bryan

Replace Server 1 with one of the dedicated Linux Firewall distros such as IPCOP www.ipcop.org . Then you can stick Server2 behind it. This setup will still allow you remote access into your W2K3 server using Remote Desktop Web Connection as long as you redirect the correct ports on your IPCOP.