You should not delete this file. Sleep and Hibernate work together in Windows 7 and Windows 8.
Windows 7 has a mode named hybrid sleep, used on desktop computers. To quote Microsoft:
Hybrid sleep is designed primarily for desktop computers. Hybrid sleep
is a combination of sleep and hibernate—it puts any open documents and
programs in memory and on your hard disk, and then puts your computer
into a low-power state so that you can quickly resume your work. That
way, if a power failure occurs, Windows can restore your work from
your hard disk. When hybrid sleep is turned on, putting your computer
into sleep automatically puts your computer into hybrid sleep. Hybrid
sleep is typically turned on by default on desktop computers.
Also, on laptops, if your laptop battery charge gets critically low while the computer is asleep, Windows automatically puts the laptop into hibernation mode.
Therefore, do not delete this file, unless you turn off both Sleep and Hibernation in your active power plan.
For more information on Sleep and Hibernation, I recommend reading this FAQ: Sleep and hibernation: frequently asked questions.