I've been using linux off and on for over a year now and I am wanting to turn an old computer into a gateway for my LAN to replace my router. The machine has 2 NICs, one which will connect to the Broadband modem, the other will connect to a switch.

From what I've seen, it looks like Debian is my best choice for this computer, features I desire:
-DNS Server (I know how to configure Bind, I think...)
-DHCP Server (looking for a good tutorial on this that is relevant for my setup)
-Advanced Firewall with port forwarding control (no idea where to start on this)
-2 of the machines on the LAN are Windows machines and 2 are Linux machines, do I need to install a Samba server for all machines to be able to use this server as a file server?
-Web Server with Mono (I've configured IIS a number of times but never actually used any other web server)
-FTP Server (easy)
-SSH Server (easy)
-One printer is directly attached to this computer via a Parallel Connection, do I need to install a Printer Server for other machines to use this?

I have googled numerous times for relevant articles, but constantly seem to find articles that are out of date, incomplete, or conflicting and just confuse me. If anyone knows of any up-to-date, accurate articles for any of the above topics or has experience doing this, I could use a push in the right direction.

Thanks!

You might want to look at dnsmasq instead of a complex bind setup. Shorewall is a great configuration file managed firewall that can do port forwarding; Guidedog / Guarddog are a pair of GUIs for firewalling / port forwarding; and see also Firestarter. The website debian-administration.org has great articles on this sort of thing; e.g. http://www.debian-administration.org/articles/23 and http://www.debian-administration.org/articles/343.

I use Gentoo and I highly recommend it mostly because of their documentation.

http://www.gentoo.org/doc/en/home-router-howto.xml

The base install for a gentoo install is very basic: command line only, no extra daemons running around cluttering things. Perfect for a simple router. Useful stuff can be added as needed.