Hi Norma,
Character dining experiences are not covered under the Disney Quick Service Dining Plan. Of course you can have a magical vacation at Walt Disney World without a character meal. However, I can suggest a way for you to have one of these experiences without paying an exorbitant price. Did you know that breakfasts at the character dining experiences are much less expensive than meals at those same restaurants later in the day? If you are paying out-of-pocket for a character meal, I highly recommend that you reserve a table in the morning. (You can do so by calling 407-WDW-DINE). For instance, breakfast at Chef Mickey's or the Crystal Palace is a reasonably priced way to enjoy a lovely buffet while interacting with the Disney characters. If you have children in your travel party, I believe that a character dining experience is a worthwhile investment. However, if this is not in your budget, I guarantee that you will still have ample opportunity to meet Mickey and his famous friends.
As for planning your itinerary, you are certainly welcome to leave those plans until your arrival at Walt Disney World. However, if you need suggestions for an itinerary before that, feel free to post some follow-up questions to the Moms Panel. We'd be happy to put together a tentative itinerary if you provide your dates of travel.
Best wishes to you, Norma, for a truly magical Disney adventure!
Jill