Clicking on a group in icon-only task manager can so 1 of 3 things: 1. show exposé type display (known as a "present windows effect"), 2. minimize/restore windows, 3. show pop-up menu.

I really like the tooltips that appear when i hover a group, but i dont like things popping up on me just from a mouse movement. is it possible to have the tooltips appear only when i click a group? (and i can then go on to click on a tooltip to select a window)

Have you tried disabling the tooltips in the Task Manager applet settings and seeing what effect that has?
I suspect it isn't possible to get the tooltip styled selector to show except when it is being used as a tooltip...

Yes disabling it means the mouse over behaviour is no longer there but I can't choose the tooltip selector for my group click. Its a great way to navigate because my mouse doesnt have to move far from the group I hovered and I get a small preview of what I'm choosing.

Okay, to get the behaviour you desire you will need to file a feature request i'm afraid. It is not possible to configure the Icons-only task manager to act in that way at this time i'm afraid.

submitted here: https://bugs.kde.org/show_bug.cgi?id=319531