Which time is better to schedule breakfast, lunch and dinner at Table service restaurants? The time you enjoy more and the time that doesn't interfere with you theme park planning... For example: Breakfast at 8:00 am, lunch at 1:00 pm .. dinner at 6:00 pm ??
Two separate questions you've asked:
1.) time you enjoy more,
2.) time that doesn't interfere with planning.
Breakfast:
You either 'Rope Drop' or eat a 'proper' sit-down breakfast. Disney restaurants are not open at 6am so that you can then scurry to a Park. You make a choice: 1.) create the time to enjoy your meal, or 2.) maximize Park time by attending Rope Drop.
In some instances, you can eat inside the Park before 'official' opening and jump-the-line (so-to-speak) when the Park opens. However, since Disney reserves the right to change Park hours, sometimes this turns out to be a losing strategy.
But if you create some time - breakfast (and photographs without waiting on line) with Princesses, favorite Characters, and/or a brunch with a view of Magic Kingdom - all are uniquely Disney. Magical.
Lunch:
Unless enjoying time away from the Parks in Disney Springs, there is no place I 'recommend' for lunch. Best advice for lunch is eat early. If you want Qwik Serve and wait until after 12:30, you are going to stand on long lines just to order your food. Sit-down reservations have to wait until the first-round of diners have eaten, and so-on. Eat at 11am-11:30am. But if there is something uniquely Disney available, that makes sense too.
Dinner:
Some of us enjoy Signatures. Some of us, not so much. Some folks will go out of their way for food at Disney. Some folks won't be bothered. Some folks find value in Dining Packages that offer 'free' tickets. Some folks are quite happy to arrive early to secure their seats. Some folks are done with Parks by dinner; others are just getting started after a day enjoying Resort activities. But we go early to give ourselves after-dinner options of fireworks, more rides, etc.
There are countless ways to Tour Disney.