Samba---> It's meant for file sharing. ( ***USE THIS***)
SSH ----> It's meant for remote administration of ur server.
Telnet----> Never, never use this. (IT'S 100% INSECURE)
Iptables is meant for packet filtering stuffs (FIREWALL-ing)
So overall to make ur network work nice
I suggest u make ur linux box:
1) DHCP Server,
2) Samba File Server
3) An Apache webserver
4) IP Tables is up running.
5)MRTG (Multi Router Traffic Grapher -HEARD B4?) It's optional but nice.
Try not to make a box to be multi-Server if possible.