Hi, guys. If at some point in the future I (totally lost my mind and) wanted to try running a half marathon at WDW, which one would you recommend, and what time of year does registration usually open up? I remember hearing that it fills up quickly…
It would be my first time, ever. But on ABC last night I saw some scenes of folks running into MK and it looked like SO MUCH FUN! And a way to really celebrate achieving some health goals. 
Sign up for email updates,link at bottom http://www.rundisney.com I started volunteering at Disneyland races last year & did my 1st 5K last year’s ToT 10 miler weekend. Did my 2nd 5k a few weeks ago DL half weekend; the oldest person doing this one is 99 years old. Coming up I’m doing 5Ks for Avengers, Star Wars & Tink weekends & doing my 1st 10k during Star Wars. AP holders get to register before general public, I check twitter for RunDisney or Disneyland AP holders(for DL races). Good luck! It’s a lot of fun. Even gave @GrownUpLilo her DL half medal. 
They’re all fun!
If you’re a lady, the princess is a great first half. Fun course, you get to run through the castle, great theming and lots of first time half marathoners. (If you’re a guy, maybe s little less fun).
The half during marathon weekend is almost the same course, and I’ve heard the atmosphere is great that weekend, and really runner focused.
I’ve never done the wine and dine half, but will let you know on 60 days how that is! It’s different cause it’s a night race, but I hear the after party is the best.
In general, you’re right, the races ate filling incredibly fast, like you need to register as soon as it opens, which can be a little annoying as that’s up to 8.months before the race.
Also, have you considered starting with a 5k or 10k and working your way up? I’ve only done one Disney 10k, but they might be even more fun as you sometimes get proportionately more time running in the parks.
Also, you don’t have to run! You can walk them too, as long as you can maintain a 16 min/ mile pace.
Also, there are a lot of run disney liners, a lot of us hang out here, if you have more questions, or feel free to PM me.
Thanks you guys! I have seen that other thread but it is getting so long I thought a new post with a specific question would be easier.
Is there a particular 5 or 10 k with lots of in park time you would recommend?
As an example, for Wine & Dine, under Runner info, Course, they will show the map for each race. As @Grown suggested, start with 5K then progressively move up. Run Disney
I did the Princess for my first half and it was excellent!! So much fun, incredibly well organized and supported, and nothing could beat running through MK! Registration for 2015 was in July this year. You can sign up on runDisney website for an email that will remind you when registration is opening for any event, or follow them on FB/Twitter. Whichever you choose, I agree it’s a good idea to get some experience in a couple shorter road races before a half. Given how expensive Disney race events are, I’d suggest looking for some local 5Ks and 10Ks to try out - they are usually much less pricy. Good luck!