If you have an ADR before a park opens, then you are only limited to going straight to the restaurant....nothing will be opened and there will be ropes and CMs directing you in the direction that you have to go. In MK, you can only walk down MS and go either to the Castle for CRT or to Crystal Palace, at AK you can go as far back as TH is in the park, and as for Epcot there are ropes and CMs waving you on not allowing you to walk into the pavilions that are on the way to Norway. We have never done the DHS character breakfast but I am assuming that it is exactly the same way as the other parks. However, do slow down and take in the atmosphere and also take pictures along the way....we have gotten our best pictures before the crowds are in the park in the early morning. Enjoy!!