Being an advanced amateur photographer, I've proven a LOT of "orb images" to be nothing more than internal lens reflections from a bright light source in the picture or just outside the frame of it. I've got quite a few photos that show more interesting things going on than "orbs" (one looks like an orange transparent space station floating in the corner of the photo with comet Hale-Bopp in the center of the photo. it was quite by accident, but it's a zoom lens and the porch light in the bottom corner opposite it is clearly the source of the reflection which is actually inside the lens but appears in the night sky to the left of Hale-Bopp which I was photographing at the time. It looks like a ghostly space station, though and it's not 'faked' in Photoshop or anything else. I've posted a link to it elsewhere in orb threads on here as examples.
However, the reason I disprove them so much is that I did experience seeing something that looked like glowing orbs in my bedroom on two nights in a row BEFORE I went to sleep. Both times they flew across the room and the first time one flew right up in front of my face. It looked like a little glowing shape in the light, almost like a person and then darted off through the wall. I wasn't "on" anything or drinking. It happened again the 2nd night (one orb and it ignore me) and I never saw one again. But this tells me that just because MOST cases are frauds or mistaken/misidentified phenomena (usually ignorance on camera lens flare phenomena), that doesn't mean it ALL is. Mythology got ideas of "pixies" from somewhere, whether it was swamp gas, something outside our normal vision capability that somehow enters into it once in awhile or a side effect of this all being a computer simulation like the movie The Matrix, you can't really KNOW for sure. We're not born with instruction manuals and our understanding of the universe is quite limited. People, especially scientists, who think they know everything and can explain EVERYTHING and come on here telling people how stupid they are to believe they saw paranormal phenomena or ghosts or UFOs, etc. are reacting out of pride and arrogance and I often wonder what their true motives are seeing they often seem to be trying to convince themselves as much as anyone else that said given person MUST be mentally ill because there aren't any such thing as ghosts!
In any case, to answer the original poster's question, I'd say I don't believe in any of it or disbelieve in any of it and that's simply because I cannot trust my own "senses" here. I know from our own computer simulations that ANY of this COULD POSSIBLY (within our own limited knowledge of physics even) be FAKED through the Brain In A Vat/Matrix/13th Floor concept. And if you can't truly 100% trust reality, how the heck can you judge it or anything strange that happens in it? We see a very limited range of electromagnetic radiation. String Theory posits additional dimensions, possibly even additional spacial dimensions (possibly being that inhabit those that to them we are like the idea of "Flat World" to us). All this judgmental crap comes from a need to solidify our own rational universes in our own minds. If one doesn't want to believe there is anything else out there, they will try to convince everyone else the same. I don't play those games. If I can find a rational explanation for something, I prefer it. But if there is no rational explanation, I don't deny other possibilities (unlike some) because I know I don't know everything there is to know about this Universe and our place in it, let alone what happens after death, etc.