I got a prompt for windows update and it is update of "Windows Malicious Software Removal Tool"
Do i really need to have "Windows Malicious Software Removal Tool" update..... even if i use Kaspersky internet security?
You don't "really need to have" the MSRT in the sense that you don't "really need to have" Kaspersky Internet Security. As long as you are computer literate enough you can avoid getting viruses. I have been without AV since Windows XP SP2 and haven't got a virus yet.
So in that sense, you do not need it. However, I have seen the MSRT remove viruses that commercial AV does not.
In my opinion, if you are a home user it does not hurt to run this tool. It takes 5 or 10 seconds when running automatically from Windows Update, it will only take longer if you download the standalone version and let it run for 2 or 3 hours.
If you are using Kaspersky Internet Security, then you don't need Windows Malicious Software Removal Tool because Kaspersky protects your system from malware, spyware and adware.