To start, I installed Ubuntu 11.10, I disliked Unity and then installed the Xubuntu session on top of it. I only say this to make you understand that I have this problem in both sessions.
Whenever I click on the hibernate option, or the suspend option, the screen goes black and then starts to hibernate/suspend. The problem, though, is that it seems to hang when it hibernates.
The first few times that I tried to hibernate, I got a blinking underscore in the top left of the screen. After awhile the underscore would stop blinking, and that's when it seemed to stop.
I then followed the instructions in this post Fix Hibernation Issue in Ubuntu 11.10
Now when I click on hibernate the hibernation begins, it seems to save the image, and then it seems to stop, the same thing I thought had happened originally.
The screen goes all black and in the top left it says:
Looking for splash system... none
s2disk: Snapshotting system
It stays on this forever and I end up having to just shut off my laptop.
I hope the provided information helps, I'm not sure what the problem is, whether I'm just not waiting long enough for it to hibernate, or if it's something else. I'm quite new to Linux and just starting to get a slight grasp of things.