Linux network upgrade

Hi, I have been asked to centralize some services and make data protection tighter on a client?s network. This is to be done with 2 RedHat Linux machines providing synchronized accounts, file and printer services to 12 Windows XP clients.

I have also been charged with the deployment and implantation of policies for data storage, handling and access. Because of my limited understanding of Linux, can someone offer any advice towards the planning?