I agree with everyone else, but will add, don't think the ART is a good alternative. In the mornings they run you all over creation and back..so that you could spend anywhere from 15 to 30 minutes getting to the front gate. In the evenings it is slammed, and you may wait over half an hour just to get on...and then you have another 20 or 30 minutes or so because, again, it goes all over before getting to HoJo.
If you've got a long trip planned, splurge for a cab. We did the morning we went to Goofy's...it was only $5 or so. VERY much worth it if you're on day 5 or 6 of a vacation!