Picked Other - I’m cool with blizzards. They aren’t just the most common disaster here*, but they’re the only one. I live on the most stable, boring tract of land ever. 
*Okay, we did have some tornados. Before 1960. They were not Death Rays.
I voted tornadoes.
They’re common where I live, and I’ve gone through a few. Like hurricanes, and unlike earthquakes, you get a good deal of warning, and there are reasonable steps you can take to protect yourself when they’re happening. Moreover, and unlike hurricanes OR earthquakes, they are very focused, so the odds of it missing you are better.
I don’t fear tsunamis at all. I live in Minnesota. Unless a comet hits Lake Superior, I’m good.
Of those things that might reasonable be expected here, I fear tornadoes the least. I have experienced them. There’s usually some warning. I’d actually be safer at my cabin than here in the Twin Cities suburbs. Up there, I built a 6-inch thick poured concrete with rebar blockhouse (roof included) that will withstand anything short of an F-5.
I would have said tornadoes up until I lived in Austin,TX and they had the F5 that hit the town of Jarrell about 40 miles to the North. My original thought had been, "meh, they don’t tend to do a lot of damage, and you can get resources to the people who are hit by them right away, so very few people die. But when you see something so strong it sucks the asphalt from the street and you see a transmission in a tree, that scares the crap out of you.
I’ve otherwise spent most of my life in L.A. or San Diego, though, so I’ve experienced plenty of earthquakes, and indeed, almost all of them barely get noticed because I assume it’s a heavy truck going by somewhere. So far, so good, so they don’t scare me. Yet somehow I know if a big one ever struck and my house collapsed on me, I’d be screwed because everyone else’s house would collapse on them too. So I’d eventually die an idiot, and to add insult to injury, my cat would probably eat my face.
If it makes you feel better, there’s no “probably” about it.
As a life long California, having lived through Loma Prieta and Northridge, as well as dozens of smaller quakes, I’m pretty blase about the whole concept. The minor ones are kind of fun, in somewhat the same way Winston Churchill once described being shot at and missed “the greatest thrill a man can experience.”
Floods don’t seem particularly scary to me, even though I know they can be dangerous. Even the flood of '86 that forced my parents to abandon our house, seemed more of an expensive inconvenience than a genuine danger.
Hurricanes are kind of similar. Intellectually, I know they can be devastating, but emotionally, it just seems like “raining hard, only more so.” It doesn’t have any sort of psychic resonance with me. That would probably change if I ever lived through one, I expect.
Volcanoes seem more like something out of fantasy fiction. I know they’re real, and can be extraordinarily dangerous (Krakatoa, Pompeii, Yosemite) but it just seems too Hollywood to really be worried about.
Tornadoes, on the other hand, despite being something I’ve never seen, hold pride-of-place in my mind as the most terrifying thing nature could do to you.
For me it was a tie between Tsunamis and Blizzards. Blizzards because I’ve been through and survived many of them. Tsunamis because I live in the middle of the Rockie Mountains and if a Tsunami gets me way up here you are all fucked.
Earthquakes. I’ve lived through a lot of them and my ancestors have lived through bigger ones, including the 06 SF. I’m prepared for them and know what to do. Even a big one is survivable. Avoid coastal areas and swampy lands and landfills. Stand in a doorway. Don’t panic. Keep a towel handy.
I’ve lived in California my whole life and have never felt an earthquake, despite living in the Bay Area for several years and right on the San Andreas for a long time. I’ve always been at the wrong end of the state or something.
No, earthquakes don’t scare me too much, and I’m always puzzled by people who swear they would never live in CA for fear of them. These people are frequently from Tornado Alley or New Orleans or some equally terrifying place where you never know what will happen.
I’ve experienced one moderately shaky earthquake and never want to experience another. It was the one time in my life I have been absolutely, mortally terrified.
I lived through a storm that flooded NJ last March all by myself without electricity and with a full cast on my arm.
I can live through anything.
Depends on what you mean by “fear”. And “experienced”.
Seriously, though, if you mean fear for my life, then I’m least afraid of floods, which I have experienced. Go up = you win. Your stuff is history, but unless you got caught utterly off guard (which can definitely happen, but is rare around here) or do something incredibly stupid, you’ll be fine.
If you mean fear of being affected at all, then I’m least afraid of tornadoes. I’ve seen the aftermath of a couple of tornados in Arkansas (but not the twisters themselves, hence the question about “experienced”), and many streets were quite literally laid out like so:
[Unharmed building][Unharmed building][Pile of rubble][Unharmed building][Unharmed building]
…and so on through the winding, but contained, path of destruction. If a hurricane (was in Ft. Lauderdale in '92, thanks), earthquake, or flood hits your area, you’re going to get hit one way or another. Tornadoes seemed to be pretty much a crapshoot…albeit one hell of a price to pay if you lose.