So you have 44 machines in your department or am I reading that wrong? At any rate you can only do what you can do regardless of the number of machines.
I've purchased thirteen UPS's over the past year as replacements for ones that died due to a power surge.
If you're having UPS's die due to a power surge you're buying crap. Sorry, but those cheap UPS's at most chain stores are junk. They aren't protecting anything and in fact are costing you needed money. To get any real protection you're going to have to spend $$. Right now all you're getting is a false sense of security.

Depending on the monitor brand and model, 5 to 6 years old is getting ancient. Now if they're working great and have sufficient size for todays work place OK, if not I would upgrade those along with the machines.

If you do it right you'll be the hero of the department and the envy of the others. That's providing they are just patching things as you were looking to do at the beginning of this thread.

As far as shifting to Windows 2000 server and discarding NetWare that's even more reason to scrap all the old tired machines and move to the 18th century in hardware. That's not a knock on Win2000 server it's just bandwidth and production and a lot more enter into what you're trying to accomplish.

Good luck.