This is best done on a newly installed O.S.
Open up the Registry by clicking "Start", "Run" and typing Regedit and clicking "OK".
Make sure HKEY_LOCAL_MACHINE is highlighted and click "Edit" on the toolbar then click "Find".
In the box that pops up type
Regedit will find it, so double-click the word and type in the box the new address you would like.
Above ProgramFilesDir is another word called
double-click this word and type in the same address as you did for ProgramFilesDir, but include "Common Files" at the end.
Continue searching for ProgramFilesDir, there should be at least 4 of them. Change all of them and all of the CommonFilesDir then re-boot and all newly installed programmes will default to that new location.
You will of course still be offered an alternative.
Any programmes you installed prior to this change may need to be re-configured.
If you just want to move the My Documents folder you can right click on it (either on your desktop if you have it showing there, or on the XP Start Menu), and choose Properties. There's an option to move the target folder - to another drive if you want.
Not so sure about the Documents and Settings folder with profiles in it though.
After viewing the settings you are able to change for folder locations using Tweak-XP and Tweak UI I do not think it is possible to move the location of the entire "Documents and Settings" folder. I think to do this you would have to edit a lot more than one value/key and it is probably not worth your time. Good luck.
Ep, glad to see you come back and tidy up...did want to ask a one day favor, I want to enhance my resume , was hoping you could make me administrator for a day, if so, take me right off since I won't be here to do anything, and don't know the slightest about the board, but it would be nice putting "served administrator osnn", if can do, THANKS