Okay, let's try the zoom tool. Aim the mouse pointer (and it does look like a magnifying glass, doesn't it?) at something you might be interested in, like the "Program Files" folder, and click the left mouse button. Zoop! The folder gets closer to you, and you can see more detail. Now click the right mouse button. Zoop! You're back out again.
(If you have a lot of free space on your disk, make sure you actually point the mouse at something interesting. Zooming gets you closer to whatever you point at, and if you point at nothing, you get closer to nothing. But if you do, you can always use the scrollbars to pan over to your data, or you can just click the right mouse button to zoom back out.)
Try clicking in various places in the display with the left and right mouse buttons to see what happens. Again, we'll wait.
Just to clarify what's going on here: Wherever you point the mouse, when you click the left or right mouse buttons, you will see the display zoom in or out around the point where the mouse is. So if you want to see something in higher detail, point the mouse at it and click. Just that simple.