I'm another mom who has gone to WDW with just the kids. I took my 7 and 5 year olds in December on a trip and stayed at POP. The only drawback was what everyone else mentioned: you can't go on the big rides. But that was ok, I've been to WDW before, and as you can see, I'm going again. Since I had 2 children with me, we couldn't go on ALOT of rides. My 7 year old is afraid of drops, so we couldn't go on a few rides that have small drops. My 5 year old was too afraid of Soarin', so we had to skip that one.
Before we left, I went over the rules firmly with the children. They were complete angels the whole trip. Even at the airport! On the way home, our flight was delayed 6 hours, so we had a LOOOOOONG time at the airport waiting for a flight home. The kids were still great.
The only thing I would have done differently was choose a monorail resort. We stayed at POP and when the kids were tired in the evenings, it was hard to keep them awake for the bus ride back to POP. I couldn't carry all the "stuff" and 2 sleeping children! lol.
We did Hoop De Doo for the first time on our last trip. The kids loved it!!! Your ds will love it too!!
Mary