I've experienced earthquakes, hurricanes, derechos, floods. I don't fear them (what's the point?), but I pay attention to tornado warnings and prepare for heavy rains or windstorms, snowstorms because we sometimes lose electrical power from trees coming down in the area.
The most unsettling, so far, was a relatively minor earthquake that occurred very early on a Saturday morning while I was on the 14th floor of a building in NYC, watching the coffee in a mug on my desk react to what I was feeling in my stomach and the seat of my pants, and hearing the rest of the building above me creaking. With no clue, of course, how long it would last. It was less than 10 seconds, but it seemed way longer just because I didn't know when it would end.
The scariest so far up here in the boondocks was straight line winds (forecast, thank God: I went downcellar) that went through about eight years ago and laid out a 60-foot cherry tree in my meadow, like it was a flimsy ol' strip of lath. Just BLAM and there was fifty feet of timber on the ground, the trunk snapped off like a toothpick at an apparently weak spot about 12 feet up. The same wind took pieces off the top parts of a black willow tree and drove them into the ground six, seven inches like so many javelins, twenty feet away from the tree itself. Ferocious thing. There were tornado warnings in the next county over, I guess we were the practice run that afternoon. I was down cellar listening to the wind throwing tree limbs and stuff at the cellar door and back of the house like, yeah, Godzilla.
Assuming one survives any of the events in the poll, I have to suggest that the nastiest thing to clean up after is a major flood where your place is not condemned and so needs massive scrubbing down with bleach and water and replacing (if even possible) everything soft that got wet. Anything else that is salvageable has to be bleached and rinsed clean. Very yucky.
I don't live where my place could flood like that, but I've helped people clean up after such floods and it's just horrible. People lose treasured things (books, papers, photos), so the cleanup is depressing, you keep finding stuff you can't save. It's usually too dangerous to hang onto any nice linens and clothes that got wet, plus everything starts to stink after a few hours, so imagine a few days... weeks... no matter the precautions you take, you have to be concerned about your health while you work through the cleanup too. So on floods: not fear, exactly. Just loathing!