That same screen happened to me, so I took it to best buy to get it fixed, opened up the laptop and it booted up: Solution: Take it to Geek squad, they don't even have to do anything its just magic, like the PC wants you to get embarrassed
I've ran into this problem before. If you still have the original software disc from when you purchased the pc, you can factory reset it which will fix this. If you have not done so already, also try manually restarting the computer (unplugging or removing batteries)
I know, they just tell you to reset the Pc and thats it. It's just funny how whenever i have a problem and i show it to someone, the problem fixes right away and makes me look like an idiot. When i was little My playstation 2 wasnt loading up so i told my dad to come see....(you already know what happens)
The error message says UNMOUNTABLE_BOOT_VOLUME , just plug that into google and there are a lot of results talking about how to fix it