You should be able to do this through your Desktop Environment, I will assume
that it's GNOME Fallback it is the default. If you cannot find what you are
looking for in the Gnome Control Center > Mouse & Touchpad > Touchpad and
then disabling "Tap to click", you can check directly in GNOME's registry:
doing "gsettings list-schemas | grep touchpad" gives
"org.gnome.settings-daemon.peripherals.touchpad".
Otherwise, it is best to look through synaptics manual(if your driver is
controlable with synaptics) and the following arch wiki article to generate
an appropriate configuration file to put in /etc/X11/xorg.conf.d/ :
https://wiki.archlinux.org/index.php/Touchpad_Synaptics#Frequently_used_options
Could you also give a little more info? (device, desktop environment,
previous configuration)
