My son was dx'd just after he turned 2 yrs old - a year ago yesterday actually. I'm very sorry to hear your other daughter was dx'd as well. I'm sure by the time you go to WDW next year you will be a pro at handling 2 with diabetes but right now it must be overwhelming.
William uses an insulin pump and if that is an option for you I highly recommend it. You won't have to worry about carrying insulin/syringes, etc into the parks (or anywhere else - we do keep those things in the room for emergencies, site changes, etc). He can eat like a normal kid and I had forgotten what that was like. Eating what he wants or on a schedule just isn't an issue anymore.
He also has a life threatening peanut allergy and other allergies so dining is sometimes a challenge. We hope to go in May and already the folks at disney have gone out of their way to be helpful...emailing me lists of peanut free items and calling me about other dining issues/questions we have.
I highly recommend the Children With Diabetes website at
http://www.childrenwithdiabetes.com - the chat rooms there are invaluable. And they have their annual conference THIS summer right at WDW at the CSR in July just after the 4th. Any chance you could make it? I went to their pumping conference in Washington, DC last labor day weekend and it was fantastic. Very inspiring to see all those kids having a wonderful time and doing a great job of dealing with diabetes. And your kids (if old enough) get to meet tons of other kids with D and the kids activities are fantastic - they never want to leave. They also have childcare for very young kids too - and siblings are welcome (D or non-D). Here is a link:
http://www.childrenwithdiabetes.com/activities/orlando2005/
Suzanne - I'm so sorry you too are having to deal with diabetes. The first few months are overwhelming but it does get better. Please check out the CWD website - the chat room can be a life-saver! I also recommend the books "Sweet Kids" and "Understanding Diabetes" (the pink panther book). The entire text of that book is online at
http://www.uchsc.edu/misc/diabetes/ud10.html You can buy both at amazon.com among other places.
I'm also happy to have you pm me with any questions.