If you want to disable the "Take Tour of Windows XP" that comes up after you install WindowsXP, then follow the below tips.
Click on the "Start" Button.
Select "Run"
Type "Regedit" and press enter.
Go to "HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Applets\Tour".
Create a new "DWORD key" called "RunCount".
Give it a value of "0".
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