As a July 4th vet for years, I can tell you that the restaurants in the parks, and immediately outside the parks will fill up faster.
Try to decide what park you will be going to on that day, and plan accordingly.
For example, I will never eat at Cape May Buffet on July 4th again!! It was overcrowded. Many people came in from Epcot to eat, and you had to wait on lines forever at the buffet! (Any buffet will be more crowded with longer lines if all the tables are taken.)
Also, if you eat earlier, say 5pm, you are better off than say at 6 or 7pm. Many like to have a later dinner, and those slots fill up fast.
We went against our own advise last year, and ate at LeCellier. We had a PS that was booked far in advance, and yet when we first got to the restaurant, they told us it would be an hour wait!
Showing absolute dismay, suddenly a table opened up. But many others were turned away, or told there was a long wait.
Good luck deciding! A nice choice might be Palio's for you. Great Italian food, and usually not crowded at opening which is 6pm. Yet it is still within walking distance of MGM and Epcot.



