If you feel the menu's in Windows XP are taking a long time to open, this is what you need to do, to make them load faster:
Click on "Start" menu, followed by clicking on "Run"
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In the "Run" window that opens, type "regedit" in the text box and click on "OK"
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In the "Registry Editor" window that opens, navigate to:
My Computer\HKEY_CURRENT_USER\Control Panel\Desktop
On the right pane of the window, locate the key:
"MenuShowDelay"
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Double click on "MenuShowDelay" and in the "Edit String" window that pops up, you can safely set the "value data" to "100" and click on "OK"
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Close the Registry Editor window.
Next, Right click on your Desktop, select "Properties"
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In the "Display Properties" window, under the "Appearance" tab, click on "Effects" button
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In the 'Effects" pop up window, uncheck the box before "Show shadows under menus" and click "OK"
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Click "OK" to close the "Display Properties" window too.
Reboot your computer to see the change in effect take place.