I am fairly new to *nix systmes apart from using an IP-COP machine and playing with that abit and doing a little programming on Sun Systems when doing It at unit however recently have been employed in property and can't believe what people pay for windows file servers /PDC that don't work and need a good reboot every few days. At home(parents small business) a PDC was never needed, but seeing the situation at work i went searching and had the same problems as everyone else with the major distros ie. redhat/suse/ the list goes on in the past, so i thought about the novel approach of turning my ipcop box into a file server/pdc by loading smaba. When doing a little research and deciding it would not be a secure thing to do given my experience, i was about to give up again when ....
I found "SME server" by E-smith. (http://contribs.org/
The are up to version 6.0.1 and is 5 year + tested distro (light weight 345mb iso) and out of box supports software raid mirror with pretty much any two harddrives, or you can use hardware raid.
Features: - https admin and text based console admin + ssh (light weight no x system) but only installed with samba 2.2.8a. However, out of box however worked fine for me as PDC/file/Print server with xp pro clients and roaming profiles but only found it a couple of days ago still giving it a good bashing.
Best of all, I just poped the cd in, and without any problems i had it working on my AMD XP2000+ 512MB file server (just put in a new hdd for the install) and BOOM!. No probs no fuss. It will run on min requiremetns and acts as full firewall gateway/routher/dhcp/dns/file server with ftps remote access/full mail server with Basic user managment but very customizable and scaleable.
I think for a single "Server" system for 3 - 100+ systems, SME server is most certinally worth a try in my opinion but out of the box aimed at SOHO users with some mods, could do what ever you want as based on RedHat 7.
Thats my 2 cents.