1. If you're looking for CRT in the am you need to call at exactly 90 days out when the lines first open and take any time available to you. These PSes run out quickly, so you won't be able to choose a time.
2. For Fantasmic it depends on your eating schedule. Most people like to have a later PS that's more around "dinner time", but I personally prefer to eat around 4. I'll eat a snack for breakfast, a light counter service lunch, my FDP PS for dinner around 4 and another snack in the Fantasmic theater.
3. I've just heard that the Garden Grill has begun taking PSes again, so assuming the Ice Cream Social still exists, you should be able to call at 90 days out and make your PS.