1) If the room is ready, I would head to the room , organize it and lay down for a few hours....then up and head into the parks for a few hours, dinner and depending on how your feeling fireworks, getting on the time zone...This works for us when we go the red eye route... Not our favorite, an extra day of vacation makes it worth it... we also upgrade our airline seats, so that we can at least rest more leg room makes a ton of difference, I normally cat nap, DH can sleep some... to ensure that we can get into our room, we have even booked a extra day, with super late check in so that our room would be ready on arrival...which is what we did when we went to Paris last year, we arrived at 6:00 am, we did put everything in the room, we thought that we were good to go, so we walked the block and half to the Arc de Triumph, and then found some breakfast, this is about when the jet lag started really setting in we had been up 24+ hours at this point, so we found the mono-plex ( grocery style store) and got what we needed, and walked back to the hotel, and went to bed, got up at 4:00pm, and got ready, and went out for several hours, dinner, and back to bed by 9:00pm, and we were good to go the next day...
2) If the rooms is not ready, check the bags, grab some breakfast and coffee, let the coffee work its magic... Head for the parks, hit some rides, I would personally stay away from the thrill rides, lunch, maybe some shopping, or a few rides, head back to the resort, grab your bag, head to the room... get settled and see what everyone wants to do... I would just stay at the resort swim, relax, grab a QS dinner, you can eat in the food court, take it and sit pool side, or even take it back to your room. Get some sleep and you should be rested and ready to go for the next day...
I would not make any ADR's as you really are not going to know how every is feeling...