Basically, do *not* move stuff around. You're free to move your own files to and from the Desktop folder or within the Documents folder etc., but you shouldn't *ever* move/rename/delete folders generated by the system. Search this forum for threads called "HELP! I renamed my home folder now I can't login!" and similar to see the havoc you're creating.
Mac user since 1987. Running Mac OS X 10.8 Mountain Lion on a MacBook Air 11" & an iMac 27" and whatever's newest for my iPhone 4s, iPad 3 and AppleTV 2.
Apple Certified System Administrator 10.6, Apple Sales Professional 2008-2011, Apple Certified Mac Technician.