It is sad. (Disclaimer: only watched the first video, figured the second was more of the same.)
Back in the day, I would relish the opportunity to have an intellectual discussion such as this.
What the kid got wrong is that he's obviously not trained properly. First, you find common ground. Find out what the householder believes. Then, talk about what you believe.
When the householder didn't seem interested in learning more about what you believe, you can then say, "Well, isn't it wonderful we live in a time where we can have discussions like this?"
Depending on the reaction of the householder, I would then say, "No one has all the answers. I personally believe the Bible has satisfying answers and provides comfort for a lot of these existential questions." I would then read a comforting passage or a passage that showed the Bible contained sound advice on living life.
I then would thank the householder for his time, if he was still railing on about evolution, and offer to call back at another time to have another in depth discussion.
What I was taught in Pioneer School is that it's okay to have an intellectual spiritual discussion. Obviously, if the person is just being argumentative or aggressive, the direction was to not waste your time. But in the case of the first video, it seemed to me that there was a genuine interchange of ideas there, and that poor, ill-equipped bloke looked like a deer in the headlights.