We took both of our daughter Nov of 2002. Our oldest was 2 years and 9 months. Our 2nd daughter was just 3 months. Just to give you an idea of our perspective, we had been to WDW about 5 times in the past dozen years. Up until this trip, always without kids.
First, going with kids is much different than going by yourself (or just with adults). You will not be able to cover near the ground you could without kids. With kids, you will have to sacrifice your agenda for your kids. Our 2 year old and 9 month daughter would occasionally decide that she was just tired. And she slept thru dinner at Cinderella's castle (tried to wake her, but she would not move), Dumbo (actually was asleep on the ride!!!), and found some of the simpliest things amusing. She loved riding the bus from Port Orleans to the parks. She would have been satisfied riding the buses, monorail and boats all day. She loved the parades, the characters and the shows.
Will they remember the trip? Our 3 month old certainly won't. Our oldest daughter, now 4 still talks about it. But she also confuses a trip we took to a carnival with the WDW trip. There is a good chance that neither will remember the trip, especially if we go again (which we are tentatively planning, falll 2004).
I am not a WDW freak. I love to go but we also go on vacation to other places and enjoy them as well. WDW is great for an active vacation, horrible if you want to relax. Even worse if you have kids and want to relax on vacation. I was so happy to get back to my high stress job and work some long hours. To contrast things, we in 2003 we spent a week at the beach in Hilton Head (Marriott Grande Ocean).
My advice, know what you are getting into. Your kids will be tired. You will tired. You will be cranky. Your kids will be cranky. The look on my daughters face when she met Cinderella at Toon Town is precious. He description of the singing dolls on Small World is unforgottable.
If you bring your kids, let them enjoy it. If you put their interests above your own, everyone will enjoy it more. If you want to take in WDW and all the grown up attractions, bring a grandparent or leave the kids. For me, I'd have a hard time explaing to my kids that I went to WDW without them.
Regrets? No. We'd do it again.