Your Windows XP system probably has the Browse Folders setting configured to Open Each Folder In The Same Window in the Folder Options dialog box. However, sometimes you may wish to open a folder in a separate window. For example, you may want to have two windows open in order to use drag and drop to copy or move files from one folder to another.
For these cases, there’s a little known keyboard trick that you can use to easily open a folder in a separate window without having to change the Browse Folders setting. Simply hold down [Ctrl] as you double-click the folder. When you do, the folder will open in a separate window.
Keep in mind that this tip only works in folder windows in which the Common Tasks pane is visible. If the Folders tree is showing, this tip won’t work.
Note: This tip applies to both Windows XP Home and Windows XP Professional.