At some point a program, when you did a diagnostic start up,(in error) has attempted to access a very specific memory block that contained Licensing data that Vista was protecting. Vista decided it was being hacked and momentarily entered a Non-Genuine state but almost immediately returned to a Genuine state. Unfortunately, when Vista enters a Non-Genuine state, it adds that the Non-Genuine text on your desktop and once Vista is back in a Genuine state, it can take up to 2 reboots for the Text to be removed.
I suggest going to click here and click the Validate Windows button and then reboot 2 times. The Non-Genuine text should then be gone.