[Jeordiewhite]

That is pretty hard to determine what is wrong when numerous things can cause a pc to do that.
There are ways to fix it but it would take some skill to get someone by your grandma to fix it.
While reinstalling isn't always the best answer, it still should fix the problem.
However it boots into windows correct and is operational for a few moments?
Then going into safe mode and putting rem's in front of any start program starting up wouldn't be effective.
It could be a driver or possibly a program starting up that has messed up or even windows is botched.