Entering Vista’s Task Manager

Task Manager shows you the programs, processes, and services that are currently running on your computer. You can use Task Manager to monitor your computer’s performance or to close a program that is not responding.

If you are connected to a network, you can also use Task Manager to view network status and see how your network is functioning. If more than one user is connected to your computer, you can see who is connected, what they are working on, and you can send them a message.

In Windows XP to enter the Task Manager you used to press CTRL + ALT + DELETE, but in Vista to get task manager  hit CTRL + SHIFT + ESC instead. You can also open Task Manager by right-clicking an empty area on the taskbar and then clicking Task Manager. (from Microsoft)