The Napa Valley Vintners have a great website that’s just chock-full of information on everything from events and history, to grape varietals, and of course, wineries.
They even have this nifty little Winery Finder tool. An option on which is Family Friendly.
While there aren’t necessarily reviews posted, there are a lot of great details on each winery.
Who: The trip planners; Napa aficionados
What: An excellent resource on many things Napa Valley
Where: http://napavintners.com
When: 24/7
Why: To learn, discover and narrow down the overwhelming number of wineries to a list that suits you