Edited to simplify after a recent re-install and noticing several steps are no longer needed
Just thought I'd pop by again to say Macs Fan Control can run with Windows 2000.
Firstly you will need to check whether you can actually find drivers for your Mac model or attempt to use XP drivers.
My model (Macbook 4,1) was bought 2nd hand so I could run "retro" music applications, so I was in luck. If anyone needs me to post the drivers for all my hardware I will happily do that here.
You will need to follow this guide to make an ISO with support for ACPI under windows 2000.
http://forums.macrumors.com/threads/win ... ss.202695/
After getting the install completed and your drivers working (I can't get the iSight working but everything else does - if anyone can fix this I'd be super happy) you will need the "Windows 2000 UUR" (Update Rollup with additional patches) and then "Chrome2K" tool to set the 2000 registry to windows XP. This is described in this video showing an install of firefox, follow this same method for installing Macs Fan Control:
Finally to get Macs Fan Control to launch and work (as we have no bootcamp support and thus no information to pass to Macs Fan Control from the registry entry that BootCamp would leave)
Create a shortcut in the program folder, edit the command as:
"C:\Program Files\Macs Fan Control "/skipcheck /minimized
The "/skipcheck" part dismissing the registry and allowing direct access to the Fans.
added "/minimized" as it gets annoying having pop-ups on first boot
This is one of those posts that won't apply to all people and only people with a need to run 2k on Apple hardware, but I hope it helps someone.