Weird shit

I got a problem in which I can't delete a file becuase it is "supposedly" being used by another program, I even stopped many processes  that could be using it and still can't delete the file. I really need to delete this because its unnecessarily taking about 5 gigs of space. Please help me and don't flame.

google a program called unlocker

when you turn on your pc, start clicking on F8 untill a black and white menu apears and select "safe mode", after it loads go back to that file and delete it

pagefile.sys?