Vista - Destination folder Access denied

I am having trouble arranging the start menu as another user in vista. I get
an error message destination folder acces denied. You will need
administrator privelages to continue. So i hit the continue button but the
same message comes up again. Isnt' there anyway to change various details as
another user. Why wont it let me enter a password or something like that. I
have UAC disabled also and i defragged the disk too. Thanks for any help