Loud bangs: balloons, party poppers, fireworks, toy guns, anything that bangs in the theatre. I very rarely go to the theatre, because there's always the risk of this. If there's a gun to be seen on the stage, I am paralysed with fear in case there's a bang. As a child I didn't like it when sausages were referred to as "bangers"; I got the idea that they really could bang loudly.
Birds that flap their wings noisily; I get uneasy near pheasants, in case they fly off noisily. I can handle pigeons, although they scared me as a child.
Electric shocks; not because they might be deadly, but the sensation. Static shocks freak me out; when it's the sort of weather when they're likely, I take great care to avoid them, by touching metal things with my sleeve. At secondary school I did not volunteer to make my hair stand on end with a Van de Graff machine, and I refused to take part in the whole class holding hands to experience a shock. Somebody also described a "violet wand" to me: I almost freaked out just hearing about it.
@Angelonia Re the Secret Garden scene of everyone dying, in one of the films that scene is quite scary. Everyone's rushing along in a panic, and Mary is screaming "give me my doll!", and you see the doll burning in a fire. In the same film, when she's creeping round the Manor to look for Colin, there's a storm, and lots of scary-looking statues and paintings are lit up by lightning. I get the shivers thinking about that.