Javaws.exe is opening multiple times on windows task manager and using lots of cpu. What are issues behind uninstalling?
You should check what programs are using the Java Web Start and then install an antivirus, because it's possible your machine is heavily infected with malware. You can run AdwCleaner or Combofix. The issues behind uninstalling might be connected with software functionality. Apps that need Java Web Start won't function anymore, therefore you will have to install the package again.
Always download Java from the official website using the following link: http://java.com/en/download/win8.jsp