To avoid errors openmosix will do best on it own network ip range. The default ip is 192.168.0.xxx. The master ideally has 2 nics one for openmosix use and one for communication with other networks.

10Mbps LAN is to small for 25 computers. 100Mbps is better. 1000Mbps is best. A switch over a hub is preferable.

Clusterknoppix/Quantain/KlusTrix will set-up it own dhcp server. Best not to mix it up with another dhcp server. Sys. Admins generally dont like uknown/multiple services running. See my first sentence.

What I'd like to do eventually is to have all the PCs PXE boot off one server and have them all running openMOSIX right away. Is this doable?
Yes, if your computers support pxe booting. check the bios. You will also need to know the network driver of you network cards.

To check the status of your openmosix box type:

Code:
/etc/init.d/openmosix status
You can also do an:

Code:
/etc/init.d/openmosix restart
and check for any error messages.

As for your "real" question, the openmosix website has community contributions section. There is plenty to choose from and growing all the time.
johnb