A. Could work as long as the focus remains on the zombie bite victim struggling to keep his sanity between the uncertainity of a possible transformation and surviving his back-then allies and now enemies.
...Huh, now that I'm saying it aloud, sounds like the concept of an inverse I Am Legend.
Thing is, some have tried to give that angle at least as a subplot of their movies; problem being that most attempts failed miserably as the execution was just plain stupid. (ex: "Oh, he won't change into one of them! He's a vegetarian!")
B. Unless that zombie is Nemesis, it just doesn't work.
This video summarizes pretty well what makes zombies work:
http://penny-arcade.com/patv/episode/zombies