I just installed 11.10. One of the standard things I do on a new install of Ubuntu is change the action taken when I hit the prtscn key. By default the action is to take a screenshot. I change it so that it takes a screenshot by area.
Here's how I do that in earlier versions: system>preferences>keyboard shortcuts Add Name: Take Area Screenshot Shortcut: gnome-screenshot -a Then click printscreen. It will ask you to disable the normal screenshot. Say yes.
Here's what I tried in 11.10 settings>keyboard>shortcuts go under custom shortcut Add Name: Take Area Screenshot Shortcut: gnome-screenshot -a All seems good so far. I see a new row that shows disabled. That makes sense to me because I haven't yet assigned a key to it. But here's where I get hung up. If i click the prtscn it actually takes a screenshot. If I hold prtscn down for 3 seconds, my computer gets bogged down and when it finally recovers I have to cancel over 20 screenshots that it has taken. So I figured the problem is that I first need to disable the default screenshot shortcut. So I went there and click backspace, but no go.