Our beloved server, cupid, has two network interfaces for Internet and LAN.
We have used that server for about 5 years, since Debian
The server is the Internet connection for 13 Windows-based workstations
and four notebooks.
Installed packages include samba, php, apache2, mysql, postgresql, postfix, clamav, amavis-ng, spamassasin, bind9, vsftpd, and tools like iptables, mrtg, squid, sarg, mailman, etc.
I chose Debian because of apt-get, and the better package management compared to make install in BSD or yum/urpm for RPMs.