We were here this past week. Quick caution on the path. If you are an early morning runner, their sprinklers are on and the path is VERY slick in some places (specially near the park in front of Marriott and the marina). The run from Aulani to Marina is just under 3 miles and is an excellent run with beautiful scenery along the way.
You can also run outside of Aulani, starting outside the lobby. That run takes you in front of all the resorts and around the golf course and is about 6 miles. IMO it is not as fun with lots of people to try to run around.
Morning runs are very pleasant and almost therapeutic. Due to time diff, we were up at 5 am almost every day and got in good runs. Enjoy your time there.