From a command prompt, just change to the folder containing all the empty folders and enter the following:

FOR /f "tokens=*" %G IN ('dir /ad /b /s') DO rd /q "%G"

The command "rd /q" will be executed on every folder, but "rd" only deletes empty folders -- "rd" does not delete non-empty folders.

Welcome back to 1995!

If you use perl on Windows, you've probably got at least one script that you'd like to be able to put on your Desktop and drag-and-drop files onto to perform some function on the dropped files. There are at least two ways to accomplish this.

1. If you've installed Active State Perl, every perl script with the ".pl" file extension on your system is associated with perl. You can make every one of these perl scripts a drop target by creating a Drop Handler as follows: Create a new registry key "shellex" under the "HKEY_CLASSES_ROOT -> Perl" key with a default value of {86C86720-42A0-1069-A2E8-08002B30309D}. You can do this manually, or save and run this .REG file to modify your registry automatically.
   • Note, however, that the filenames passed to your script by this method will be DOS 8.3 filenames, not long Windows filenames.
   • Link: RE: drag'n'drop onto desktop icon ??? (By Jack)
2. Alternatively (or in addition), you could create a shortcut to Perl and add the path to the perl script as an argument, e.g., in the "Target" field of the shortcut properties, type "C:\Perl\bin\perl.exe" "\PATH_TO_YOURSCRIPT\YOURSCRIPT.pl". The shortcut will automatically be a drop target whether or not you implemented the registry change above. (You could also create a shortcut to wperl.exe, rather than perl.exe, and eliminate the DOS box.)
   • Link: Re: drag'n'drop onto desktop icon ??? (By Bill)

Warning If you use Registry Editor incorrectly, you may cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that you can solve problems that result from using Registry Editor incorrectly. Use Registry Editor at your own risk.

1. Click Start, click Run, type regedit, and then press ENTER.
2. Navigate to the following subkey:
   HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced
3. Right-click the right pane, create a new DWORD value, and then name it EnableBalloonTips.
4. Double-click this new entry, and then give it a hexadecimal value of 0.
5. Quit Registry Editor. Log off Windows, and then log back on.

These steps disable all Notification Area balloon tips for this user.

There is no way to disable balloon tips for specific programs only.

Source:
HOW TO: Disable Notification Area Balloon Tips in Windows XP

For XP Home: (Keith Miller) Go to Start/Run/Regedit and navigate to this key:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa

Value name: limitblankpassworduse, Type: REG_DWORD, Data: 0 (disabled) 1 (enabled)

For Home: Run Scheduled Task without a Password (Line 67)
http://www.kellys-korner-xp.com/xp_tweaks.htm

Source:
Windows XP FAQ

In Windows XP, when you try to open a file of unknown type, Windows offers to search the Web for the appropriate program to handle the unknown file before offering to let the user choose which program should be used. To bypass this annoying step, use the Group Policy Editor, which should be located at C:\WINDOWS\SYSTEM32\GPEDIT.MSC, navigate to:

Local Computer Policy->
  Computer Configuration->
    Administrative Templates->
      System->
        Internet Communication Management->
          Internet Communication settings->
            Turn off Internet File Association service

Then open the Properties dialog and select the "Enabled" radio button.

1. Locate the file "outlook.hol" on your harddrive (usually in C:\Program Files\Microsoft Office\Office10\1033)
2. Backup your current "outlook.hol" file (for example, save as outlook.hol_original)
3. Save the new outlook.hol file in this directory
4. Open Outlook and delete all holidays (try viewing by category)
5. From the "Tools" menu, select "Options". On the "Preferences" tab select the "Calendar Options..." button, then the "Add Holidays..." button on the next screen and select the United States holidays