Try repairing Corrupt Windows System Files with the System File Checker. Windows + R key will bring up the Run Dialig Box. Enter
sfc /scannow in it and hit Ok.
You will need your Windows CD in Hand, just in case the utility asks for it. If it does find corrupt system files & replaces them, the try uninstall - reinstall Java & see if the prooblem is resolved.
Did you go to http://java.com/en/ and Click "Do I have Java?" to see if your JVM is actually working?Ravi.