Sounds like you have a damaged control panel function file on this machine. Try this...Do a search for *.cpl in you Windows/System32 folder. Move ALL of the files out of this folder into another folder of your choice....just remeber where they are
Try and open Control Panel now....if it works, then try and move these .cpl files back into the System32 folder one at a time. Try and open the Control Panel again after you move a file back into the system32 folder. You'll find the one causing the problems and then you can just replace it with one from your 2000 CD or from teh i386 folder on your machine.