wikiHow article about How to Disable Simple File Sharing in Windows XP Home Edition.
Depending upon your specific needs, you can get Windows XP in any one of five editions. Of those five, the choice of the two best known ones - XP Home and XP Pro - will differently affect your ability to share files. Both the Home and Pro editions have their advantages and disadvantages. There are also 5 well known editions of Windows Vista, though the distinctions between the Home and Business (not Professional) edition groups will be less relevant to Windows Networking issues.