Have you considered exorcism?
I'm not a Netware expert but you might want to try to backtrack and get some of the history of the machine. Did it work okay on the network and then "all of a sudden" blow up? I've worked on a few church systems and while I have the highest respect for men and women of the cloth, I also find that their computers are usually the most messed up systems imaginable.
I'd verify that the system is totally functional before I installed Netware. Start it up and let it run as a stand alone for a day or two to satisfy yourself that the system is okay. If you've got a copy of Norton Utilities it would be a good time to do some diagnostics. That way you know that you've got a good Windows install and good drivers, etc.
Then if the Netware messes the system up again you can nail your problem down. Given that the system runs okay off the network you have to suspect the Netware. What are you installing Netware from? I've seen a couple of cases where the distribution CD's that are still sitting next to the computer are five or six generations out of date and you really should be on the net looking for and installing the latest and greatest drivers.
If that doesn't work I'd throw a couple of extra bucks in the collection plate and spring for a new hard drive. I personally don't think that's your problem but 6 gig doesn't hold a lot of sermons anyway.
Good luck
Dave