-Overall, the "best" Disney resort is the Grand Floridian. The hotel is a monorail stop away from the Magic Kingdom, it has one of the nicest restaurants in Central Florida, the atmosphere of the hotel is elegant and luxurious but not over the top, it has a beach area/spa, and the rooms/service are a notch above the other resorts.
-My personal favorite is the Grand Floridian. See reasons above.
-In the Epcot area, my favorite is Beach Club. The atmosphere is casual, the architecture is beautiful, the pool area is fabulous, and the hotel is literally closest to Epcot.
-The two most popular are probably Wilderness Lodge and Polynesian, for their immersive themes, family friendly activities, and proximity to MK.
-My least favorite is Animal Kingdom Lodge. It sucks in comparison to genuine African game lodges.
There are so many resorts to choose from and so many factors to consider, that everyone could have a different favorite or least favorite. Life experience, personal interests, favorite theme park, budget, etc will all have a great influence on your favorite hotel.