Laptop not starting up

[Eurox]

Yesterday I went out and bought a new webcam, and after it installed and restarted it came up with a blue screen saying "windows shut down to save your computer from damage, restart and check to see if you have enough memory" so i started it in safe mode and i had plenty of memory but everytime i started it up normally it kept coming back. So i restored it to the day before and now its so slow and ive lost half of my music and things like McAfee arnt working. Anybody got any ideas?