It really is impossible to predict such a matter. I mean, think about it, its nearly impossible to think about how earth would be impacted if the heat from the interior of the planet that powers plate tectonics were to suddenly cease to exsist, or if that heat never exsisted in the first place, because that is how planets are formed.
One thing is certain however, life wouldn't be the same without plate tectonics; in one case, the constont transgression/regression, sue in large part of tectonic forces acts as a evolutionary pump forcing life to evolve. EXAMPLE: the evolution of plants from marine to terrestrial settings. Without plate tectonics, life would certainly be dramatically different.
~This is an edgucated guess. :) I hoped i helped. :)