In my keyboard the print screen key is very close to the backspace key, and whenever I want to press backspace, instead it takes a screenshot. How can I disable the print screen shortcut?
You can try changing it via
System Settings → Hardware / Keyboard → Shortcuts → Screenshots → Take a screenshot
To disable the shortcut, click the row so that it shows "New accelerator" as shown below and then press the backspace key.
I disabled it with prejudice, because every cursor key event popped up the screenshot dialog and gnome-screenshot is the culprit. I'm mostly using LXDE and couldn't find where this is configured - the usual Linux problem - so I delete
/usr/bin/gnome-screenshot and replaced it with a executable file with just
# in it. This may not be efficient but does the job.