If you’re getting really annoyed – like I do – whenever you’re typing something and you touch the touchpad by mistake, which transfer the cursor to some other window on the screen, then this article is what you’re looking for:
Open a terminal and type in:
synclient MaxTapTime=0
If this successfully disables the tap to click, then add a new startup entry (Settings->Settings Manager->Session and Startup->Application Autostart) where the command is:
bash -c “synclient MaxTapTime=0”
Source: http://ubuntuforums.org/archive/index.php/t-1875057.html