Exceptional Process

Guys,While experimenting with processes i found that SYSTEM IDLE PROCESS cannot be right-clicked,i means u cannot even try to kill it,or set its priority

• open task manger and goto process tab
• There you will find a lot of process running by many accounts
• You can try to kill or set the priority of any process by right clicking it
• But try for System Idle Process.You cannot even get the pop-up

Even i dont no why?Even Iam in the search of this answer.Now dont says that it may be a critical and very important process,thats why windows doesnot allow you to kill it.But what if we want to set it to high priority