I don't now if they have anything available still, but we stay at Samoset in Gilford. They are condo's.They have a small beach with sand and a pool as well if the lake is too cold or rough. I have three kids as well and we save some money by using the kitchen for some meals and it is close enough so the ride to the Weirs isn't that bad.
Here is a link to their website
http://www.samosetnewhampshire.com/