Definately check out
Dreams Unlimited! Not only do they offer super service, but they also have various incentives for using them (ie. stateroom credits etc).
We booked through DU and booked our air seperate as we used a free ticket through frequent flyer miles. We also saved a TON of money over booking with Dis....not always the case, but it was in ours.
Verandahs are not necessary, but I will warn you...once you have one, it will be hard to cruise withOUT one!
I am not sure about the most desirable category for a family of four...we are a family of three and are very comfortable in the cat 6. they do have the cat 11's which seem popular with other families not desiring the verandah.
We have stayed on deck 5 and found it very quiet, we will be on deck 6 this time, so not sure there. On different cruises I have booked according to the following: mid-ship, deck situated between two room-only decks...in other words, not below or above a public area, and close to, but not right by, the elevators.
Keep in mind that ANY deck on the Wonder/Magic is close to the action! Deck 3 offers the bar/lounges, deck 4 has dining and theaters, deck five has kids clubs and movie theater, deck nine has resteraunts and pools...etc.
Hope this helps. Please check out Barb's site and Dave's site as mentioned above...they are a wealth of great information!
Happy cruisin'
Lisa