Windows XP Professional
A quick look: Windows XP Pro is the business-grade edition of Microsoft's most popular operating system.
XP® Professional Edition is the most popular release of Microsoft's® Windows® operating system. Windows XP Pro is the most full-featured edition of XP, containing all the features of XP Home, as well as file encryption, support for use with Windows Server 2003, and Remote Desktop for accessing your computer away from the office. Building on the platform of Windows 2000 Pro, XP offers a more secure and stable operating system, with improved peripheral support and helpful system recovery features. Installation of this software requires a blank hard drive or a hard drive format.