Hi Andy! I don’t have exact experience with black Friday in Orlando, but wanted to comment anyway. It actually makes me a little bit sad that black Friday is a piece of American culture that others want to experience (not your fault!), but others might disagree. I personally would not suggest black Friday with young children. The mall will likely (hopefully?) be closed on Thanksgiving day and might open late in the evening, say 8pm. Each mall is different and the themes seem to shift a little each year. For example, I live in Massachusetts and it is illegal for the mall to be open on Thanksgiving, so it opens at midnight.
Many of the crazy, incredible deals would require you to be waiting in line either very late Thursday night or very early Friday morning. They also are usually on larger electronic items or toys, etc. Which are things I imagine you can’t easily transport home in your suitcase! What are you looking for sales on? There will likely be clothing sales for the entirety of your trip as stores try to start the Christmas shopping earlier and earlier. Perhaps Friday evening will be a little less crowded but still offer some sales. Otherwise the “mall floodgates” are open on Thanksgiving and they will probably be crowded for the rest of the month.