Ok, if you have a windows, here's how to do it.
1. Download Windows Process Explorer.
2. Open it.
3. Find javaw.exe
4. Right click all of them and hit "kill"
5. You're done
Hope this helped, if it didn't I can help you through with skype. Just message me on PM me for skype on youtube @The Ender Cast.
KTHXBAI