Turning off tap on Synaptics Touchpad

Hi All,
I'm running Vista on a Toshiba Portege M200. The M200 has a Synaptics
Touchpad. I have installed the Synaptics Vista drivers from
http://www.synaptics.com/support/drive.cfm (version 9.1.0) since the
Toshiba site doe not list any Vista TouchPad drivers.
Two things are wrong.
Firstly every time I start my laptop I get an error message "The
publisher could not be verified. Are you sure you want to run this
software?" for "C:\Program Files\Synaptics\SynTPEnh.exe. Unchecking
the "Always ask before opening this file" check-box has no effect next
time I restart. How do I tell Vista I want the software to run without
the dialog?
Secondly, and more importantly, I need to turn off the 'tap to click'
functionality since I'm forever accidentally clicking things. But the
Synaptics set-up utility does not recognise that I have a Touchpad.
The Device Manager lists a "Synaptics PS/2 Port Pointing Device" but
the Synaptics settings do not give the Touchpad specific options, like
disabling tap.
Any help would be much appreciated.
Cheers,
Tim.