Account Gone

I turned on my computer a couple weeks ago and found that everything on it was gone. A window pops up before everything loads and says that it can’t start the computer with my settings. I have no idea whats going on but only a week before that happened windows media player was miraculously uninstalled. if someone could explain what happened and how to fix it, I’m pretty computer illiterate but if I’m told how to do something I have no problem.

Thank you.