I definitely would recommend Ohana's. My DH and I went there last year for breakfast (no kids, but we both love Stitch). The kids there were having a blast with the characters and even had them in a parade of sorts. I thought the food was pretty good as well, not the best, but pretty tasty. Although I could have eaten that pineapple bread for days yum.
As far as transportation goes, if it's very early in the morning I recommend a taxi or a your rental car, if you have one. We had a very early ressie about 7:30ish and decided to take the bus from AKL over to MK and then hop on the monorail. BIG Mistake. We left a solid 30 minutes before our ressies and were 20 minutes late - b/c of the monorail. The bus was no problem, but once we got on the monorail at MK and stopped at the Contemporary we got "stuck" there. I think the drivers didn't realize they had passengers because after ten minutes of sitting there, we popped out to let them know we were there. The driver was busy chatting away with the cast member at the Contemporary. Even after she saw us, we still didn't leave for several minutes. Once we got to the TTC we got off and decided to walk (another big mistake as it's not exactly a hop, skip and jump away). And to top it off, the monorail driver got nasty with us and said the next stop was the Poly. We told her we were already late and couldn't wait as long as we had at the Contemporary. As soon as we got off, she took off. Go figure. Fortunately, the CM's were very nice at Ohana's and honored our ressies. Lesson learned.