Jay:
Flame is likely on to something, but please provide more info. When the blue screen of death (BSOD) appears, what *exactly* does the error message say? Does it have the word STOP followed by 0x000000yy (where yy represents two numbers or a number and a letter)? If so, please write down the stop error number and let us know what it is.
If there is not a stop error, please write down exactly what the error says and leave a reply for us so we may look it up. One of us will tell you what to do next.
Also, if you know, please tell us what happened just prior to the BSOD. Did your son/daughter install a new game? Did you add a new expansion card? Do you have some evidence that the computer is infected with a virus?
Regards,
Doc