Collapsible Taskbar Buttons (Windows)

Those of you that use Windows XP will likely be familiar with the taskbar and its support for collapsible taskbar buttons when the taskbar gets a bit too crowded. Windows XP seems to do a pretty good job with collapsing like items, but there's a feature that I find useful but missing. Maybe there's a way to do it, so if you know how, please share.

Here's a screen capture of a Microsoft Outlook task with 6 open e-mail messages. Windows has appropriately collapsed them into a single button and reports that there are 7 tasks (1 for Outlook and 6 for the open messages).


Now, we know that the Outlook task is the parent, and the 6 open messages are children. What I want to do is close out all the children tasks, but keep the parent open. There is a Close Group option when you right click on the collapsed task group, but that closes everything including the parent.

Is there any easy way to get back to a single parent task open without having to resort to closing the group and then re-launching whatever is the parent application? I understand that sometimes Windows will group tasks where there isn't a parent... that's fine, as I don't expect that there's a mind reading OS that can figure out what subset I want closed. However, this seems like a nice feature that is lacking.

Anyway, help me if this is in fact possible and you know how to do it. Thanks.