In Windows 98, if you have your folder set to open a folder in a new window each time you double click on one, your desktop quickly becomes cluttered with too many windows. There's a quick way to shut them down in a single mouse click. Here's how:
1 - Hold the Shift key down.
2 - Click the "X" in the upper right corner of the last window you opened, and all the "parents" of that window will close.
There's also a way you can minimize all open windows without closing them in a single mouse operation.
1 - Right click on any blank area of the Taskbar
2 - Select "Minimize all windows" from the pop up menu.