Journal: Novell Netware to Open Enterprise Server or Active Directory

I am the lone IT guy just starting at a school where they still use Novell Netware 6.5. I have zero experience with Novell anything, and come from a 5 year experience with Active Directory on 2000/2003. I've had some experince with FreeBSD, but not as a directory server. There are approximately 300 client machines and they are a mix of Windows XP Pro and some XP home.

Here's my question: Upgrade to Open Enterprise Server or switch to the more familiar Active Directory even though I would have to learn Server 2008?