Dear Ramu2020,
this value should be stored under; "HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\Uninstall".
Please refer to the following discussion for more details.
viewtopic.php?f=2&t=5959Anyway, you should consult the MS SQL documentation for more details.
Last but not least, I really don't understand why you want to remove SQL Server from the target machine. Even if the product has been installed by your application, it should be not removed when your application is un-installed. Other installed application may use it and this is the reason why, this is not a recommended operation.
Regards