It is possible to change permissions in Win2K if the file system is NFTS but not if your harddrive is formated in FAT32.
actually, you are all kind of wrong.
you are not able to change permissions for registry branches using regedit on windows 2000, only win xp, 2003 etc.
however, its not all doom and gloom. if you need to change permissions in windows 2000, follow these steps (to the letter, dont do anything other than this as it may knacker your computer, also forgive the caps, thats how it appears on screen):
type regedt32 and press enter
this will open up a slightly different screen with loads of windows, click on the one marked HKEY_LOCAL_MACHINE on local machine. Scroll down to SOFTWARE and double click it. Scroll down to PCSUITE and highlight it, now click on security on the top menu bar and choose permissions. Make sure everything has full control etc.
there you go, that should work for you.