To use screenshot the whole screen takes a screenshot of your entire screen, current window only takes only the current window and capture an area of the screen lets you select an area interacetively. To start the interactive area left click and then drag the mouse in a rectangle to select the area you want to take a screenshot. There is also a delay for the screenshot you can set like a timer for a camera in the bottom right corner of the screen.
To have your titlebar and frame around the window on a current window is a checkbox on the bottom. The include mouse cursor will include your mouse cursor in the screenshot.
