[K12OSN] OT - what's the easiest route to centralized authentication and home folders?

[Carl Keil]

Hey folks,

Starting from scratch, what's the best way to centralize logins and file 
serving for a mixed group of linux (ubuntu) and Windows XP (home) 
workstations.  The school is also talking about installing a Mac.  I'm 
thinking of trying the Samba/LDAP script on Centos 5 K12LTSP.  Is there 
a better (easier) way to go?  How would you do it if you were starting 
from scratch and actually implementing thin clients was a ways off in 
your planning?  Should I go 64 bit?  The server I'm thinking of using is 
a Pentium D. 

This needs to serve about 50 students - 10 staff and volunteers
17 workstations mixed Ubuntu / Windows (for now)  - possibly all on at 
the same time.

My plan so far is to install Centos 5 K12LTSP on a repurposed 
workstation with a mirrored software RAID for the home directories.
Install backupPC on another repurposed workstation for nightly backups 
of above.
Use the Samba/LDAP script to export /home and provide authentication for 
everybody. 
I intend to use LDAP for the school's Joomla site, possibly Moodle, an 
attendance program, etc. after I get the initial server set up. 

Any suggestions?  Is this overkill for 50 students?  We have $0 budget 
for this.

Thank you so much,

ck