Displaying a list of running applications in Windows 2000/NT

Hi,

I wonder if it's possible to obtain handles of running applications in
Windows 2000/NT (this list should equal to the list of the task manager;
that is, if you select the tab 'applications'). If so, then I would like to
send a 'close' message to one of those applications.

How can this be achieved?

Thanks in advance,

Erik Boerstoel.