Hey Dave,
Welcome to the boards. If you are unsure about your choice of hotel, check the reviews on TripAdvisor. I generally use them as a guide to hotels if I am not sure about a place. We also have five kids that we take to WDW. This year we are renting a house in Windsor Hills. There are a good amount of bedrooms, plus 4 bathrooms, a private pool/hot tub, playroom, and two family rooms. Cost wise it is very economical. The only thing we dont have is free breakfast, but that is not a big deal since my kids dont eat alot in the morning anyway. We are looking forward to having several bathrooms and room enough for everyone to get some space from each other when needed. Last year we stayed onsite and it was great, but for the price you cannot beat having a whole house to yourself. Most of the vacation rental communities are very close by to Disney so traveling back and forth would not take forever. Any other questions feel free to ask and I hope you have a great vacation with your kids.