Zod's reflexes didnt really look that fantastic (unless im forgetting something) travel speed was good, but i don't see him countering Prof X thinking sleep/stop. He probably stops dead in his tracks, if he was moving to begin with.
Professor X doesn't just "think sleep" in the movies. He specifically puts his hand to his head and concentrates on someone to use his mental powers on them in almost every instance I can think of.
Well, he did freeze several rooms of people during the movies without really thinking much about it.
He did that offscreen and appeared on screen after they froze, if I'm recalling correctly. It wasn't an on-screen insta-freeze; he may have concentrated offscreen to lock on to everyone before coming in, etc.