Re: So what /should/ have been done?
Ctrl + Alt + F1 can occasionally fail if the application is locking keyboard input.
Alt+SysRq completely rarely never fails though. + REISUB for best results :)
If you're suffering from anything but a kernel panic then `RE` is usually enough to kill the application and gui allowing you to restart the desktop without having to reboot.
PS> e17 is the only window manager I know of that lets you restart it on segfault without loosing applications / window placement... which I like. :)