Here are some suggestions that I have:
1) Like others have said, base it on historical park hours. The EMH schedule is available on other threads here, but always subject to change. If you want to take advantage of EMH, book your restaurants based on that. If you want to avoid them, again I would use that schedule.
2) Get a park hopper! Then you don't have to "worry" so much about where you plan to be that day, because you can always visit AK during the day and hop to Epcot for dinner/fireworks. (as an example)
3) Plan your meals at the times you normally eat. Leave yourself an hour or so leeway, so if you call for a 6pm dinner but all that is available is 7pm, you're not *too* disappointed.
4) You could also book resort restaurants as they do not require admission. That way once the park hours come out, whether or not you have a park hopper doesn't matter as much. If you plan on dinners around 6 or 7 every night, then you'll plan your park visits around that.
5) Don't stress about it! Park hours are generally published 60 days out, but they have been known to change at 59 days, 30 days, 14 days, 7 days, etc. notice. Go with the flow and you'll have a great time!