hi
I was looking at an old project plan that I did and forgot about the other steps...
For the task duration bar for the main task (e.g. meetings - I think the default colour is black) right click on it, then click on format bar, then make sure the shape for the start, middle and end are all blank.
then right click on meeting one duration bar (should be blue) and then click task information, then check the box that says 'roll up gantt chart to summary' and click ok.
do the same for the next sub task (e.g. meeting two)
then click on the minus if you want to hide the sub tasks or plus to show them.
ZaK