Best is very subjective.
Which characters do you want? Princesses, Classic or Pooh? Are specific characters important - Mickey, Minnie? Cinderella? Ariel? Stitch? Playhouse Disney characters?
Do you want Breakfast, Lunch or Dinner?
Do you want to dine in a park on a park day, or maybe create a non-park day with breakfast at one of the resorts, followed by a waterpark and/or Downtown Disney.
What is your touring plan like? Where are you staying? Breakfastosorus might not be worth the stop if you were going to skip AK this trip. Cape May is probably out of the way if you are staying at the Poly and don't plan on a morning at Epcot or MGM.
Do you have a big preference for buffet, family style or plated?
Answering these questions and giving them a priority will narrow your choices. There isn't a lot of choice for Pooh. Likewise, if you are looking for Ariel, your choices are slim. Minnie and Donald are only at a few meals, and Lilo and Stitch only at one. Breakfast is the most available choice, choices are slim at lunchtime. Not all the resorts have meals available, and while there are character meals again now in all the parks, they are limited in some parks.
We usually make a tradition of Ohanas (and have since it was Minnie's breakfast). Mickey is there (and what is a trip to WDW without Mickey), and Lilo and Stitch now. (Minnie hasn't been there is years, though once we had Minnie instead of Lilo - who apparently got grounded by Nani that day). We do an early breakfast and usually walk into the MK right at opening, so we aren't cutting into precious park time. And we prefer family style service to buffets - I do enough walking at WDW without getting my own food. It also has the advantage of being less popular, so I don't need to call six months out to get the time I want.