There are some tips on room locations in the Tips & Trivia FAQ section of this site (
www.portorleans.org/faqs.php#POFQ-Rooms), but it really depends on what you want! Building 5 is generally regarded as the best all-round, and given your group mix the proximity to the pool would probably help. If you want something quieter, look more around building 7. Building 4 is best for parking lot access while still being close to pool & food court.
Now as for eating on 4th July... probably best to ask this on one of the larger trip planning forums such as the DIBB, but remember that it will be
very busy wherever you go and you'll
need to book 180 days out (again, see the tips FAQ). The parks will be PACKED, so don't expect to be able to come out and go back in again later if you want to spend the night at a park to see the fireworks, etc. Epcot would probably be the least packed park, and it has lots of great dining choices too. MK is great of course, but may just be too busy to be enjoyable; if you're not in there at the start of the day, you may not get in at all. So if you want to be in a park, think about places like Le Cellier or maybe France or Italy at Epcot for nice meals. Your food preferences also come into it too, of course, but Epcot offers such a wide range of foods that I'm sure you'll be happy.
Have fun whatever you choose though.
