You don't know the operating system? (windows 7, windows 8, etc...) umm alright never mind then no problem. Try this...
Hit Ctrl + Shift + Esc to bring up the Task Manager.
Then in the Task Manager, click File, New Task (Run...).
**cheers mate but i tried all these already, but when i use shift+esc it brings up a different task manager, one im not used to. there is no file so i cant hit new orr anything