If you have Windows Vista and have tried pressing Ctrl + Alt + Delete keys, to bring up the task manager, it will not work. You will be logged out first and then given a menu of choices. Of course you can choose to open the windows vista task manger from there, however why go to all that trouble.

In Windows XP it was easy to get to the task manger by just pressing Ctrl Alt and Delete keys on the keyboard. You would be taken straight to the task manager, and not logged out to get there. In Windows Vista you can now press Ctrl + Shift + Esc keys to get directly to task manager.

I would love to know why they have changed it?

Windows Vista Task Manager