Just found your thread and am so happy that you're going to get to go to Disney!!!
I've been really excited for first-timers lately, perhaps because I'm doing a group trip with just my girlfriends in the fall and one of them will be going for the first time.
I've been going to Disney since I was 8, so I loved it as a kid, but I love it JUST AS MUCH as an adult! (We're just a few years older than you.)
DH and I don't have any kids and have no plans anytime soon to have any. And we have so much fun at WDW. DH didn't go a bunch of times as a kid like I did, but we started our trips together on our honeymoon, and have gone on adult trips several times since.
We love theme parks in general, but what Disney does that no one else has really done is the theming and storyline on EVERY ride. The attention to detail is beyond belief. A roller coaster is never just a roller coaster, nothing is "just a ride." You will be so impressed.
OUR fave things at Disney:
Magic Kingdom - Pirates of the Caribbean, Haunted Mansion, Big Thunder Mountain Railroad, Splash Mountain, Space Mountain.
Animal Kingdom - Expedition Everest!!!!! (amazing!!!), Dinosaur, Kilaminjaro Safaris, both walk-thru jungle trails.
Epcot - Soarin' (we took my parents and grandmother with us in 2008 and my dad still has not stopped talking about how much he loved Soarin'), Test Track, Mission Space (I can only really do the green version of Mission Space, orange is too intense for me), ALL THE COUNTRIES in World Showcase. Seriously, you can spend a few days just visiting all the countries.
Disney Hollywood Studios - Tower of Terror (also a BIG fave), Rockin' Roller Coaster, Toy Story Mania, Lights Motors Action Stunt Show, Star Tours.
We also enjoy going to Downtown Disney for shopping and some adult beverages. Although, we also enjoy the different alcoholic offerings at Epcot - especially the Grand Marnier and Grey Goose slushies in France. mmmm......
And I'm going to post my thoughts of resort choice here on the adult forum, since some people in that other thread seemed really freaked out that you didn't want as many kids around you.
I'm not a big fan of lots of kids. My two nieces are super cute, but that's where it ends. (And I still have a BLAST at WDW.)
We own DVC (the Disney time share) at Animal Kingdom and LOVE IT. LOVE. IT. And I don't feel it's swarming with kids. And we usually go in the summer since DH is a teacher. Having the animals outside the balcony is beyond awesome. And our favorite restaurants are at this resort too. I give it my absolute highest approval.
In contrast, we stayed at one of the value resorts (All Star Music) in 2006 to save money (before we bought DVC) and after that, I vowed I would never stay in a value again. Not because the rooms weren't nice, but because it was swarming with kids. Everywhere. And the buses were horribly crowded. We bought DVC the next year. And now that we stay DVC at the deluxe resorts, the crowds of children seem greatly reduced in comparison and the buses are much less crowded. (And for those who have kids, don't jump on me about not loving kids. Just want to demonstrate to the OP that you can LOVE Disney even without having kids. I guess I feel more that I'm still a kid myself!)
You will love Disney and you will love Animal Kingdom Lodge if you choose it as your resort!
Let us know what you decide!