this is for parents of kids of all ages, including people who are thinking about being parents and thinking about what they might do... if you've got kids who aren't old enough for some of the things in the survey, feel free to estimate or make stuff up, haha 
About 18 months, but only for about 20 minutes at a time sporadically through the day. Why? Because my wife and I needed a break from the hyperactive little monster! 
His first show is Backyardigans and he really likes the singing and dancing. Then Netflix took it off Play Instantly, and he moved on to Thomas, Bob the Builder, etc.
DVDs and internet/Netflix. We prefer Netflix, because kids' DVDs are horrible for marketing crap that you can't avoid.
Haven't done so yet; he doesn't have the patience.
We've been doing that for a while now. He almost always can't sit still through the entire thing.
Cars, because we thought he'd like it so much he'd stick with it longer than most other movies we could've picked out.
Nope.
Obviously, FaceTime is interactive so much more "real" than passively observing the TV.
We don't have a tablet, but the little S steals my wife's phone all the time. He's two, but is able to swipe, launch the Netflix app, and find/start shows he wants to watch on said app.
A month or so ago, 2.
