All of us have our favorites, or maybe you're more strategic with your ride-choice than nostalgic, but what ride do you head to first when you hit the parks?
My answer will seem bizarre, but there is logic in it --
[Drumroll please...] Swiss Family Robinson Treehouse at the Magic Kingdom!
Allow me to explain. We
always begin our vacation with the Magic Kingdom, and we're
always walking into it for the first time well after rope-drop (after flights and check-in at our resort) on our arrival day. That gives us about half a day to work with, and all of our favorite attractions, and the ones for which we'll have made FP+, are in Frontierland/Adventureland/Liberty Square (e.g., POTC, BTMRR, Splash, HM). Another arrival-day tradition is dinner at Liberty Tree Tavern. That means that the best use of our time is to start in Adventureland and then proceed clockwise through Frontierland, and Liberty Square, and perhaps start on Fantasyland. That makes Swiss Family Treehouse the first attraction we reach, so we do it first. It also has a couple of other advantages: (1) as we climb higher, we get a beautiful view of the Magic Kingdom, and have a chance to re-acquaint ourselves with the layout, or explain it to any first-timers in the group; and (2) because it's not the most "exciting" attraction, it's a great way to dip our toes into touring and then slowly build the excitement by continuing with attractions like the Magic Carpets, Tiki Room, etc., before getting to the really thrilling stuff like Pirates and Splash.
On subsequent days, of course, our "first attraction" is determined solely by the desire to avoid long lines. At HS, Jedi Training (whatever it's called now) or Toy Story for DH and the kids, and RnR for me. At Epcot, Test Track (with a FP+ for Soarin') and Spaceship Earth. At Magic Kingdom, whatever headliners we haven't been able to FP+. At Animal Kingdom, Kilimanjaro Safaris, Expedition Everest, Kali River Rapids and/or Dinosaur.