Add me to the "request upper floor" camp. I'm TERRIFIED of snakes (major phobia - I have panic attacks and have actually fainted from seeing a snake) so I cannot stay in a first-floor room. Ridiculous? Probably. And yes, I know they can get to upper level rooms. And I know Florida is crawling with snakes and critters (I used to live in southern FL). And I know many snakes are harmless. I get it. It's not logical to me, either, but this is an irrational fear I've had for as long as I can remember.
I just feel better being on an upper level. I picture how Mousekeeping leaves the door open while cleaning and how easy it is for a snake to slither on in and then hide...
I've been to Disney 4 times since 2006 and I'm ALWAYS on the lookout for snakes while there. You'll never catch me walking on grass in FL. I've only seen 1 snake and that was last year at Epcot. We had just gotten off the monorail and I looked over the railing and saw a huge black one slithering across the pathway to the parking lot. I didn't freak (because I was far enough away and it was headed the opposite direction) but it did increase my anxiety for the rest of the trip.
I won't lie...the recent "snake in my suitcase" thread freaked me out! I didn't have this anxiety when we stayed Deluxe and had interior hallways.