I'm trying to make my computer to start a task when it goes idle, and then kill it when i start using the computer again. I tried for the first time windows scheduler, idle options are there but it doesn't work (beats me why).
I already tried third party tools and i was able to make an app to start when the computer goes idle but not to kill it when the computer is being used again
If you are using Win-7 you can do that in task scheduler.
Open the task scheduler, select My Task Schedules, and choose Create Task (not create basic task).
Give it a name, click the Actions tab and choose the program you want to run
Choose the Conditions tab, click on "run if idle for xxx minutes", and check stop runing if computer ceases to be idle.