I just had to fix that on my Vista laptop. I used google to find this article -> http://www.howtogeek.com/howto/windows-vista/re-enable-hibernate-option-in-windows-vista/
You gotta ask "What were they thinking?"
I have an HP Pavillion dv 9700 laptop. I want to use the 'Hibernate' option when closing the lid but I find that the only three options available are 'Do Nothing', 'Sleep' and 'Shut Down'.
How can I overcome this?