Granny,
We were there on Christmas Day 2004 when the weather was horrible, rainy and cold. It was crowded and the restaurants were running out of food to sell as they didnt expect Christmas Day to be that crowded.
That said, there was plenty to do and I found most of the kids knew the DQ etiquette, that if someone stands behind you while you are playing a game, that means they are next. Most will finish their game and step aside for the next player. The CM's dont really get involved in regulating game play but that system works most of the time. My 5 year old would sometimes push the button to play again so I would have to move him along and explain it to him that someone was waiting.
It really is worth it, especially if you like some of the more expensive games like DDR and VR games because these can cost $1 or more per play.
I found the internet cafe to be worth the cost of the $85 AP for myself, because we dont carry a computer to WDW and dont have to pay $10 per day for internet access. Our December trip was 15 nights so I was able to use the computers there quite a bit to check email and the DIS while DH and the boys played. You will have to have more patience at the Internet Cafe, because the adults dont play as well as the kids and normally camp out at the computers for hours. I admit that on my first visit I was guilty of this too, because you cant really tell if people are waiting. I am now more cognizant of it because the computers time out at 30 minutes and you have to log back in.
DQ stays open really late. Most nights until 12 am and on weekends 1 am. We would do the parks or relax during the day and spend our evenings (most times til close) at DQ.
I could really see letting the boys hang out there by themselves when they are old enough because it is self contained with food and lounges and they really dont have to leave. Our cell phones (cingular) worked pretty good in there too.