Question: How do I switch my windows xp computer from English to Spanish? 

Answer: You can't, you would need to buy and reinstall the Spanish version of Windows on CD.\n\nIf you only need to configure your keyboard, sort criteria, etc., use the Control Panel to set locale preferences.  These only work for input devices (ie, your keyboard), and not output: you'll still get titles, messages, etc., in English.
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