Your 1 must do?

[TeeterTots]

Splash mountain, Kilimanjaro safari, and ToT!!

 

[bearybubba]

Carousel of Progress for me. It was the only ride I loved during my first trip to WDW in 1987. I hated the rest of WDW back then and never wanted to go back! Now I absolutely LOVE WDW. Just went for the 10th time this past November and planning trips #11 (Dec '16), #12 (Nov '17), and #13 (Apr '18)!!!!

 

[PetePanMan]

way too many cheaters on here listing more than 1

 

[tlmadden73]

Star Tours

I went on a short trip (only two park days . .AK and MK) in Oct. 2014. But since AK closed at 5:00 pm .. we hopped over to DHS after an early dinner all we did there was see the last Frozen show of the day and then went on Star Tours (rider swapped) and then left as Fantasmic was starting.

If you ask my son (now 3 1/2) after two trips -- he would say Buzz Lightyear.

 

[pearljamin03]

Sitting at Magic Kingdom, eating a mickey bar watching the fireworks... It doesn't get any better than that

 

[DVCcurious]

Get our family picture with Mickey Mouse!

 

[nooneshome]

Wishes

 

[TI double-GUH ER]

The one thing we absolutely, positively MUST do every trip is visit the wishing well - everyone has to wish for us to be able to return to WDW!
(Of course, we frequently make other wishes too... )

 

[tstidm1]

It's a Small World because of the connection my mother has to it and to Walt. My mom went to the 1964-65 World's Fair where Great moments with Mr. Lincoln, Carousel of Progress and It's a Small World all debuted there. She still loves It's a Small World. I love it because of the soothing music that it is. That is above having a Fresh Rice Krispy Treat from Main Street Confectionery.

 

[erij11]

Fantasmic!

 

[Bullseye]

way too many cheaters on here listing more than 1

You're right on...we all have many, but the question is your number one.
Tower of Terror

 

[Deanie1]

HM in the evening - when it's dark outside. OK, one more - Kilamanjaro Safari.

 

[Planogirl]

I'll say Haunted Mansion too. That old ride embodies what Disney has done best.

 

[DizDaD7]

Ok, so this is possibly a cop out answer, and definitely has to get done if you venture through MK...

Plain & simple, The walk down Main Street!! There's something about the way it makes us feel. The sights, the sounds, the smells, the people...... That is truly Disney....
BTW there are plenty of others as well, but this immediately popped into my head...

 

[Minnie121]

Mickeys Philharmagic!! Absolutely love it. I do it 3-4 times each trip.

 

[AFwifelife]

Welcome show at MK's RD.

Brings me to tears every time we see it.

 

[snowybelle]

The MK Welcome Show at Rope Drop. When they come in on that steam train... that is EVERYTHING.

 

[Brandon's Antics]

Haunted Mansion. Even as semi-locals that visit monthly, we ALWAYS hit HM. Pretty much anything else we have a "we can catch it next time" attitude towards.

 

[CarolinaDD1997]

The one thing we ALWAYS do is go to Ohana for breakfast! Absolutely love it! And we also love watching the welcome show at Magic Kingdom, its pure magic!

Well and the ones mostly everyone loves, Wishes and Fantasmic

 

[goodeats]

I think the best thing about WDW (or even DL) is that there is no one thing that makes it great. I could go on a trip to Orlando and stay offsite and just go to Disney Springs and I will still feel like I got a Disney fix. My preferred method of course is to stay onsite (Deluxe please!) and go to all 4 parks over a week, but honestly just being on Disney property is great! Same with the attractions, there is no one attraction that if it were closed would make me reschedule my trip. I mean I guess if TOT, Test Track, Splash Mountain, TTA, Safari, AND EE were closed maybe I would.

Looking at my last 4 trips the only thing I know was the same in all 4 trips is that we rode TTA at least 5 times. So maybe that, but I still wouldn't reschedule my trip if it were closed.