Hi, Tammy!
Race morning logistics are always tough to work out. If possible, I would suggest trying to find a later breakfast reservation - 10:00am will be pretty tight.
The first thing in knowing if you'll have time to check-out of your resort prior to your Advanced Dining Reservation at 'Ohana is to know your corral placement, which has not yet been released. Even though the official race start time is 5:30am, corrals are released at timed intervals with the last corral beginning the race sometime after 6:00am.
Next, consider your anticipated running pace. Since this is your first half marathon, consider the pace you've been training at so far to calculate your estimated finish time. Also consider any stops you plan on making for photos along the course. There is not a specific time in which the race ends, however runners will have three hours and thirty minutes to finish the race from the time the last runners in the last corral cross the starting line.
If you plan on taking Event Transportation back to your resort, you can add about 30-45 mins from when you cross the finish line. Between running, traveling back to your resort, refreshing, and traveling to Disney's Polynesian Village Resort, you can see where a later reservation may be beneficial. The good news is
'Ohana accepts breakfast reservations up to 11:00am!
I hope this information helps to give you a better understanding of what to expect race morning, Tammy! And as always, you know I am here if you have anymore questions!
Aloha!
Faith