login and shutdown / log out issues

using 10.3
KDE no longer works (after NVDIA drivers install)
trying to get VBOX usb to work and changed the fstab as instructed on web: As root, edit /etc/fstab and set the gid and mode for usbfs as follows:

/sys/bus/usb/drivers /proc/bus/usb usbfs devmode=664,devgid=113 0 0

now one account can’t log in
Gnome panel does not load

another account does not load
Gnome does not hve write access to directory any more

other accounts can log in successfully
but using the gui shutdown / reboot / log out menu nothing happens
can log out / shutdown using the teminal

if I upgrade to 11 how much risk is involved? and will it resolve the above issues?

Before reinstalling you could try to rename your user’s .kde directory and restart KDE, it should go back to normal. There is probably a subdirectory that keep the settings for login only, but I don’t know which, if any.