When a preferences package, is included inside a GPO, when that GPO processes on the computer, every single one of these lines is going to be processed on that machine. The green and red lines are telling you what is going to happen with each individual setting as it gets processed.

Every setting with a green line under it will be pushed to the computer to which this preference deploys. You can change this behavior by switching those green lines to red lines, meaning those settings underlined in red will not be manipulated on the client machine. This is essential to know in cases where you only want to change certain settings within a preference, and don't want to spend extra processing power on changing all of those settings that are underlined in green by default. Once an individual setting is changed over to a red dotted line, it is completely ignored when the GPO processes on the endpoint computer.