Why when I'm working my MacBook Pro go to a blue screen

Lets see if you can get into Target Disk Mode. Restart your system and press the T key Are you able to see the FireWire or Thunderbolt icon on the screen?

If you can then your issue is within your HDD and/or the OS installed on it. I would recommend you first copy off anything important to a second system using the Target Disk Mode you've gotten your system into. Connecting via either a FireWire or Thunderbolt cable to the other system the systems HDD will appear as an external drive. Once you get your stuff off (copy or via TimeMachine) Use the second systems copy of Disk Utility to check your drive.

Let us know what you find.