There are buses running between resorts and parks starting at 6:30am every morning. They do tend to run a bit less frequently than the 'regular' buses do, so plan accordingly.
To get from OKW to 'Ohana....bus to MK, then monorail over to the Polynesian...the monorail starts at 7am.
Now...if you board the bus, and ask the driver if it's quicker to take the monorail or the boat over to the Polynesian to get to your breakfast ADR, he may actually offer to drop you off on his way by there. No promises, but maybe!!