One more question.Is there any difference in performance (or in general) between enterprise and professional version of windows 8.1 ?
None at all. It's the same codebase. The Enterprise version of Windows 8/8.1 simply includes some features that are designed for business applications. Home users will see no benefit from these.
Windows 8.1 Enterprise is Volume Licence only and does not provide any upgrade paths to retail versions. I do not know how you got your hands on that but you must remove it if you do not have a SA contract with Microsoft.
One more question.Is there any difference in performance (or in general) between enterprise and professional version of windows 8.1 ?
None at all. It's the same codebase. The Enterprise version of Windows 8/8.1 simply includes some features that are designed for business applications. Home users will see no benefit from these.