BSOD Error

Hello,

Recently, (specifically Tuesday) my PC restarted itself, previously showing a blue screen of death with a message about Physical Memory. Sure, fine. I understood my p memory overloaded, therefore restarting. However, 5 days later (today, Sunday), my PC did it again. This time, I was doing nothing much except for playing my game: Tibia. I couldn't catch what was written, however I knew it wasn't anything to do with physical memory. I only read: Your computer has encountered the following system error and needs to be restarted: (some code I didn't have time to take a look at). I've read how to uncheck the restart, but I have the following doubts:

1. Any way I can remove the blue screen rapidly to carry on with what I'm doing.
2. Do I have to re-format my PC as suggested to me by a friend.
3. Run a Virus Scan and Defragment my disk.

Please, any help or simple dedication to my thread will be extremely appreciated, especially as I'm at a time in my life where things are tending to go down the wrong way.


Regards,

Matthew.