Yep, it might sound confusing. /usr is roughly (very roughly) equivalent to "Program Files" in Windows. The /home/user directory is where the user files are; even then, there seems to be some files in ones /home dir to which the N770 is very sensitive too (like .profile). Just as one wouldn't go rendomly deleting files in c:\windows, leave most of the files in your N770 alone. They' re probably needed.