Check out the WISH (we're inspired to stay healthy) Board here on disboards.
I am a Weight Watcher and when I go to WDW, I don't really count points. I drink my water, the walking certainly helps and I try to order as many plain steak and chicken items as I can. The cs places tout the meals with the fries, however you can get a burger and drink without fries and they knock off something like a dollar. If you are on the
DDP, just ask your meal to have carrots subbed for fries. Meal sharing is always an option at any cs plase or non buffet table service place. That helps a ton. The portions are large, too large in my opinion.
If your wife wants to count points, then I would think that she can look at the menu's on Allearsnet.com. She can see the places you are going, think about what she wants to order and then go over to the Weight Watchers site (or use one of the food companion/dining out companion books) and compare similar items at other more well known restaurants. For example a plate of spaghetti and meatballs at say Tony's in the Magic Kingdom will probably be about the same point value as a plate of the same thing at Olive Garden (and you can find their points online or in those books). A burger at Sci Fi will be about the same as a burger at Denny's and so on. She can take her points ruler to figure out points on packaged foods like the ice cream bars which have the nutritional info listed on them.
And at the food courts in the mods and values, I like the grab n go sections. You can get a simple deli sandwich, fruit etc., Way less points than a burger or other fried type meal. Also, there are fruit carts at all the parks that sell fresh fruit. And pickles which are about a zero point food and not a bad snack!
In the end, its just a finite piece of time. She's on vacation and even if she goes for broke and pigs out, she'll be back home in no time and her good habits will be there waiting! And the walking and swimming (if you do that at your resort or at a water park) really do help.
Have a great trip, definitely visit the WISH Board, its been a ton of help to me and there are plenty of Weight Watchers over there that can also help answer this question!