I would call the Disney reservation line. Yes there are adjoining rooms, the only way you will be booked into two of them is if you list minors alone in one room, then you can be guaranteed adjoining rooms (this is what I was told last year when booking ours--my parents wound up not going so we didn't need the adjoining rooms after all. I personally have been to Disney 9 times and this last time was the first time we stayed on property...I will NEVER stay off-site again. We had the quick service meal plan, made ordering very easy, it was prepaid so there was no worries on who could order what or concerns over the price of the item ordered...all but your 8 year old will be considered an adult at Disney for both tickets and meal plans. You can book a long way out and pay it off as you please with no interest as long as you are paid off at 45 days from arrival. Create an account and play with their website, they do have cabins that will accomodate six and the family suites and the value resorts I think will as well...I'd have to look to make sure though. We are a family of 5 and we can do the alligator bayou rooms at POR (Port Orleans Riverside), but at 6 you can't do that, otherwise we have to go up to the cabins, suites or higher priced resorts.
join the disboards.com, disneyfoodblog.com, touringplans.com (they have a book called the UnOfficial Guide to WDW 2103), allears.net, easywdw.com, wdwmagic.com and any other forums or info sites you can find, they all differ a little, but my faves were touringplans.com, disneyfoodblog.com and the boards on babycenter and cafemom
There are rental homes in the area that would be a great choice for your family if you want to cook some meals at home and take breaks, but it will be at least a 30 minute drive to the entrance of any park, plus parking (which isn't overly cheap), and since the parks (other than animal kingdom) don't close until late, since your kids aren't small you might not want to go back to your accomodations mid-day for a break like some with younger kids might.
my suggestion is to plan everything as much as possible and make sure you get a disney lines app from somewhere (I prefer the touringplans app to others, but I just like their info and find it more reliable than others) on your smart phone if you have one, it'll make staying on schedule and seeing what lines are like post meals or post shows more easy than walking all over the park (the parks are very large with the exception of the studios).
send me a message if you'd like more info, I'll share all day long if I sit here and type.