Gautam,
Office XP (2002) and up should work without issue on Windows 7 Pro.
Because Office XP and Office 2003 are on Extended Support status, there are no design or functionality updates available for these products to address issues that occur when these products are run in Windows 7. Additionally, no more service packs will be released
for these versions of Office. For more information about the support policy for these and other versions of Office, visit the following Microsoft Web site:
http://support.microsoft.com/gp/lifeselectoff
The 2007 Office system is the recommended and optimal version of Office for Windows 7. These products are still on Mainstream support status, and they are assigned the Windows 7 logo. For more information about Microsoft Office and other products that are identified
as compatible with Windows 7, visit the following Microsoft Web site:
http://www.microsoft.com/windows/compatibility/en-us/Default.aspx?type=Software
For more information about the Windows 7 Application Compatibility List for IT Professionals, visit the following Microsoft Web site:
http://www.microsoft.com/downloads/details.aspx?displaylang=en&FamilyID=890e522e-e39e-4278-aebc-186f81e29173