Reduce touchpad touch sensitivity or disable tap-to-click unless key is pressed

Solution 1:

In the Software Center there is an application called Pointing Devices sudo apt-get install gpointing-device-settings That should have everything you need.

Solution 2:

Go to Mouse settings. Under the General tab, there should be a slider for adjusting sensitivity under the Pointer Speed category.

I don't know if there's a way to hold a key down to toggle the touchpad on and off, but you can set a keyboard shortcut to do so. Open up Keyboard Shortcuts, then press the 'Add' button and, under command, enter gconftool-2 /desktop/gnome/peripherals/touchpad/touchpad_enabled --toggle. Enter a name for the action, e.g. 'Toggle touchpad'. After applying, back in the main Keyboard Shortcuts window, under the 'Shortcut' column, enter in a keyboard shortcut of your choice.