Hi Deepak,
1 - Yes, you can use the WCE 700 BSP without the ICE. The ICE is a tool to debug the system, but it is not needed to install the BSP or run it in your application.
2 - My experience is good, but in the end, it always depend on your application if it is convenient for you to use either Windows, Linux or a different operating system. But this BSP works fine with the MX51.
3 - Not sure what you mean by Windows Certified. This BSP is certainly based in an original Windows operating system provided by Microsoft, but they don't give us any certification of any kind.
Best regards.
Jorge.