The worst is without a doubt God's Not Dead. The writing was so awful is that I not only hated the movie, I was DISGUSTED with it. It was absolutely pathethic and I hated it so much I'm cooking even when just briefly mentioning it.
"Greenburg" and "While We're Young" are likable movies. As for "Greenburg," Ben Stiller plays a character who you'd walk across the street to avoid. That doesn't mean I don't want to watch the character in a movie. In fact, I recommend both movies.