I am a WW leader and I just got back from
free Dining at Disney. I lost a pound. Here's my advice. It isn't just about going "off-plan" for a week. You'll probably find your tummy has shrunk enough that even without trying to you'll lose weight on vacation. The key is to have a post-vacation plan in place. We get very used to eating the deliciousness down there & then when we see we don't gain we unconciously think we can continue to eat that way back home.
So have a pre-vacation plan (realize you won't be totally on-plan while hectically getting things together those last few days) have a during vacation plan (like wearing a pedometer & making at least one healthy choice a day & sharing whenever possible) and a post-vacation plan (like going to a meeting within two days of coming home and getting right back on the exercise bandwagon, tracking bandwagon.) Make sure to write down your plans and have a new Winning Outcome before you come home if your old Winning Outcome had to do with "lose xx lbs before Disney World."
As for healthy choices, I found lots at Disney. I especially tried to eat healthy at breakfast and generally just had a banana. By the end of the week, if I'm being honest, I was having a banana and a chocolate croissant for breakfast so I then had to choose fruit or something else healthy for lunch. The salads at the counter service places were pretty good. Finally, if you don't like something, spit it out. Don't eat something at WDW that isn't incredible. There are just too many delish things there to waste even one mouthful on something you aren't crazy about.
Hope that helps and if you have any specific questions I'd be happy to help. WDW & WW are two of my favorite subjects!