Started my fairly new ( 7 months) 27" Imac this morning and got a very strange screen that I cannot find any info on. It was a grey screen with 6 round circles, three in the middle of the screen with animal heads in them, a zebra, a lion and I don't remember the third one. My name was under each circle, there were 3 more circles at the bottom of the screen, one was restart, shut down and don't remember the third. I wasn't able to restart from the screen so shut down with the button. I restarted and it slowly came on, and has been a little weird all day. I'm afraid to shut down - since I am in the middle of several jobs and can't afford to lose the data. Has anyone ever had this happen and what does it mean??