There is a McDonald's near the All Star Resort - it is on the right hand side as you drive to the resort gate. It is fairly big, so you won't miss it.
However, a word of caution: if you don't plan on having a car during your stay, it is a far walk. Disney transportation does not stop there. With a car, I would guess your travel time would be around 5 minutes. Walking - maybe 15.
Does anyone know if there are sidewalks along that stretch of road??