"operating system not found" Vista HP dv 6000

Hello, everyone. I've been having the same problem as many people but I haven't been able to find a good answer. I do not know much about computers etc. so I need a basic how-to-do to fix my issue with my laptop.
So when I start up my laptop, a Vista HP dv6000, I come upon this screen where it says "Operating system not found." I had one of my friend's friend take a look at it and it worked fine until I attempted to turn it off. It crashed and went to some screen (blue screen of death?). The next day, I tried using it again (wanted to transfer data to an external hard drive since I was told my hard drive was dying). The same thing happened but it had a bit of more text like something something media failed etc. + the "Operating system not found." So I tried playing around with the options and seeing if this or that would make it work again (ugh of course not...)but everything just reverted back to just "Operating system not found."

Is there a way to fix this problem without losing all my data? I don't have a CD or anything either.