Hi
You can turn Hibernation on and off through the Administrator Command Window.
Open window, type....
powercfg.exe /hibernate on
or
powercfg.exe /hibernate off
I tried running it a few days ago and my computer wouldn't shut down completely (the activity light on my computer wouldn't go off) unless I pushed the on off button, so I turned it off again.
It didn't have any effect on boot speed, my computer only takes about 30 seconds any way.
But you can try doing it both ways to see if it helps your problem.
Mike