I have a Sony Vaio VGN-NW350F laptop computer that was recently given to me. I was told that the hard drive in the laptop was new, and it has windows 8. there didn't seem to be any programs on it, but after installing a few programs (programs i have used in the past), the hard drive says that only 86.5 GB are available of 286. I know none of my programs take up that much space, so how do I figure out and fix what is taking up all the space on my hard drive??