A way to make screen corners easier to use?

I find the screen corners fiddly to use. When I touch the very top left corner I get a preview Window of what I believe is being called the App/Task Switcher. My mind automatically keeps making me move the mouse into the center of the preview to click it, by which time it's disappeared.

Is there a way to let me click the center of the preview window?

When you "touch" the top left corner -- just to be clear, you have a touch screen?

No, sorry, should have made that more clear. I mean touch it with the mouse.

Ok, I see what you mean.

Right now, if I point my mouse in the upper left corner it shows a thumbnail of whatever the previous app I was looking at was.
If I mouse downward along the edge of the screen, a black bar fills the left edge of the screen and the rest of my open apps show as thumbnails below the most recent one.

Once that black bar appears, you can mouse the center of the app you want to select.

So one solution is, mouse to the upper left corner, then mouse down along edge a little and you'll be able to click the center of the thumbnail image.

A

I found that if you right click when on the corner screen it will freeze it so you can then pick what you want and click on it.

For me quick and dirty If there is only one window there I right click and then click close without trying to get into the centre of the open window. Hope this made sense.