Depending on the day of the week....
There are days when DL and DCA are open later.... DL is always open later than DCA
On our last trip, we had a full week but on our first day this is what we did.
Arrived early and went to DCA first. Its a smaller park and we were able to sweep through it and do all the major attractions in less than an hour. There were so few people there, everyone once in a while we would look around and wonder if we were the only ones there.
Once you've done that head over to DL and spend the rest of your time there.
Others may disagree, Because DL is usually busier you may want to go there early before the big crowds. Which might be a good idea if its a weekend or a time of year when the crowds are heavy.
Another plan of attack may be to do DL first and do the big rides early, then head over to DCA since its smaller and usually less crowded, then go back to DL after dinner and take in what you missed the first time.
All this assuming you are planning to do both parks. We also have been there many times and have seen EVERYthingand had many days to come back So sweeping through was easy for us.
As for eating...we went no frills and did the usual Denny's, IHOP, Mcdonalds route and saved one special dinner...which for us was the Rain Forest Cafe in Down town Disney.
I hope you have a lot of fun!!
Becky