Want 'minimize', get 'close'; what now?

[utu]

Some magic I don't need.
Knoppix 6.2.1 on USB; otherwise well-behaved.

Somehow, my 'minimize' operations have all become 'close' operations.
I click on 'minimize' and would expect a program window to shrink
to an icon on the taskbar. Instead, the program closes. Gone for good.
Happens for all programs with all window manager types.

Probably a configuration setting, but which one, and where do I look?

[utu]

Solved.

I found this on LinuxQuestions.Org, quoting anishakau's response to an identical question there:

Quote, except for my edit '-> (Click) + Add',

Welcome to LQ !

Right click the Panel -> (Look in the resulting menu) Panel Settings -> (Look for the TAB) Panel Applets
-> (Click) + Add -> (Select) Taskbar (Window List)

Unquote.

Somewhere along the line, I'd lost the Taskbar (Window List) applet.