So, basically the problem started as this: you got tired of accidently moving the mouse while typing on your laptop, so you naviagated to the touchpad settings screen and enabled the option that reads “Disable touchpad while typing”. You thought that you did well.Then your problem quickly became this: the delay before you are able to move the mouse is much too long. In fact, it is an irritatngly long two full seconds by default. We’re going to adjust that delay and fix both your new problem and old problem with one little command.I’m using Xubuntu 12.04, but this may work for good old Ubuntu as well. It should also work for any other linux distro running XFCE. One caveat: I think that you must be using a touchpad supported by the Synaptics driver for this fix to work (although I’ve never had a touchpad not use this driver on my laptop linux installs)

Source: Configure Delay for “Disable Touchpad while Typing” Xubuntu | Computer Correct