If you want to encrypt the paging file then, since Vista, Windows has a native utility.
Open an elevated Command Prompt, and to encrypt the page file, enter... fsutil behavior set encryptpagingfile 1
Rebooting is required for this to take effect; and to turn off the facility change the final 1
to a 0
figure and reboot again...
There is a price to pay in performance terms though, because R/W paging operations take longer.
Just don't ask me how secure the encryption is, but I expect Google will know...