Fog is a multitude of packages, but those packages have their own controllers. These controllers are designed in such a way that they handle their own startup and shutdown. Of course you can also start or shutdown or restart them as you see fit as well. The simplest way to shutdown is to type the command:
sudo poweroff or sudo shutdown -P now

To restart type:
sudo restart or sudo shutdown -r now

does that computer have 32 gigs of ram, by chance?
by default, i believe windows creates a pagefile equal in size to the amount of ram in the computer.
btw, fog automatically deletes the pagefile and hibernate files before uploading the image to the server, since they will automatically be recreated and they consume a lot of wasted space.