This was of the first thing I looked upon after buying and what came out to be surprising is you don’t need any software to do this. All you need is press the button on top ( which is On/Off Sleep/Wake button ) and menu button together and a screenshot of the entire screen will be saved in the Photo album by default.
Coming to next point, if you want to shut down or turn your iPad off completely, just keep pressed the On/Off Sleep/Wake button for a bit longer. You will be prompted by a screen which will have “Slide to power off”on top and a Cancel button at the bottom.Use the options which you want.This screen says for few seconds and if you don’t press the power button for long enough it will just put the iPad to sleep.