Originally Posted by owichiu
wtf...I just tried to took a screenshot of gallery and it returned a 0 byte PNG file.
I am using CWM 18.104.22.168
It sounds like your internal storage may be corrupted. I'd try wiping everything. Like I said other people don't have the issue. It could be a rouge app that corrupted your internal, a app that has access to your internal sdcard like another gallery app. It's happened to me before on my nexus 7 (not gallery but corrupted internal), and the only way I could fix it was to restore stock factory images and wipe everything clean.
Another way, in power menu, long press on the reboot menu. You'll be given a safe reboot option. Reboot with that and see if the issue is there. Good luck.
Edit: This is safe mode