JezzBall from Windows Entertainment Pack 4

This was released 1992 and originally made for Windows 3.x.

It is a very simple game that can be played entirely with the mouse.

The following are the instructions copied directly from Help - How to Play - Overview:

On a far-off world, a new kind of atom has been discovered. It's called a Jezz, and you get paid galactic credits each time you trap one for shipment back to Earth. The Jezz atoms preserve their energy best when tightly confined, so the smaller the chamber you trap them in, the more galactic credits you acquire.
The game begins in a large capture chamber with two Jezz atoms bouncing around. With a click of the mouse, you can build a new chamber wall and trap the Jezz atoms in a smaller space. But be careful, if you don't build your wall completely across the chamber before it's hit by a Jezz atom, it won't withstand the impact.
Be forewarned, JezzBall is not just challenging and great fun, but also strangely soothing and satisfying. Once you start trapping atoms, you won't want to stop!