Our family movie night went pretty well. The youngest fell asleep by Rivendell, the oldest was pretty enthralled, the middle boy (age 7) says he enjoyed it but definitely got the heebie jeebies. Oddly, it wasn't the Ringwraiths or even the gross orcs that pushed him over the edge. It was the skeletons when the Fellowship crossed the threshold of Moria, and the glimpse of Gollum. He was pretty nervous about whether there were going to be any more glimpses of Gollum, and I had to assure him that there weren't. The trapped tomb of Moria, the darkness (visually and thematically) of the film at this point definitely unsettled him. The release of the battle in the chamber of Balin's Tomb, and the Balrog, actually helped.
BTW, Thanks for the streamload hook-up...TTT trailer was awesome, and the FOTR extended sold my wife on waiting till Nov...I let my 6 y/o daughter and 4 y/o son watch the trailer...I think they're hooked...