You can't hibernate because there is not enough hard disk space
on your laptop. Hibernation uses the same amount of hard disk space
as your RAM.
In your case, you have 1GB of RAM, which means 1GB of hard disk
space will be used for hibernation. This will leave less than 1% of
hard disk space left, making hibernation impossible. Windows need
you to have at least 5% of the hard disk to be free to run
properly, which means you need at least 5GB of hard disk space,
assuming that there is only C drive.
Please remove any unnecessary programs, backup your files in an
external media to free up disk space.
After freeing up hard disk space, your laptop should be able to
hibernate and standby again.
