How to disable Mouse Click With Touchpad on Ubuntu

This problem is really annoying. When I used my touchpad with Ubuntu, I often experienced missed-click. It's because my touchpad setting is enabled for click. And on my box, it seems the sensitivity is too high. When I move the cursor using touchpad, it often clicked mistakenly. And I know the solution for this : disabling the ability of my touchpad to do mouse click. But how do I do it on Ubuntu ?

A picture means thousand words. Therefore, before continuing to read this post, you should put your attention on the following image:
Disable mouse click with touchpad on Ubuntu

That's it. You need to uncheck Enable mouse clicks with touchpad. Click Close at the bottom of the Window and you're done.

But wait, how to open that window ?

Almost forget to explain it. You can open that Window through System then click Preferences then click Mouse menu. You'll see that Window. If you can't find the System Preferences menu, I think you should consider to reset your Ubuntu desktop to its default setting.