[ubuntu] How do I set up a network Intranet on Ubuntu Desktop?

view full story

http://ubuntuforums.org – I am running Ubuntu Desktop 12.04 LTS and want to start up a Office Intranet through DHCP. Does anyone know how I could start to work on this? I have connected wifi router with the Ubuntu Desktop machines, Now I would like to configure the internet service for the office users. Can someone please help on this regard? All Internet access will goes from the server, files and printers will be shared too. As Microsoft ISA server works. I am newbie on Ubuntu Desktop and does not know how to setup/configure. (Hardware)