Hi Srini,
Here is a example VI that will do what you want.
"This VI simulates the behavior of the WindowsStart&Run dialog box. You can enter a path and filename, and LabVIEW launches the file with its default application. Also, you can type a path, and LabVIEW launches a Windows Explorer window to this directory path. This VI works in Windows 95/98/Me and 2000. This VI uses the System Exec VI to perform these functions."
Best Regards
Johan