Reporting back: dh now says "almost all star trek is good" after having watched section secret seven.
Also, he is working through original series with the kids. Yesterday they watched the Harry Mud one and were doing all sorts of weird stuff afterwards to try and disturb my android mind apparently. No idea what they're going on about as I don't remember the ep. They also claim I am a vulcan every time I mention logic.
So my question is, what old Doctor Who episodes would you start with? Nothing too scary. My oldest is a bit sensitive, even the silicon monster in star trek was too much (bizarrely until he found out it was a mother protecting her young and then it was fine).
Oh and old sci fi films they've loved include ET and Short Circuit. We watched the Star Trek whales film with them pretty early on and that was a hit too. They're 6 and 8.