Hey Nancy!
Congratulations on your first trip!
For drinks, bring whatever you are comfortable carrying that day. The only type you can not bring in is the kind in a glass container. My family each brings a plastic, or metal, water bottle each day into the Parks. That way we can refill at water fountains throughout the day as well.
For snacks, you can bring anything into the parks that you can easily travel with that doesn't need to be heated or cooled! So, those small bags of chips, trail mix and cereals all work good. We usually bring granola bars and fruit leathers because they are compact and pack small.
One way to save some money with these snacks is have the kids mix up some inexpensive cereals, raisins and any pretzels while still at home. Let them decorate some plastic sandwich baggies just for Disney & put their "Disney Snack Mix" in. You save money & get them excited about the trip all at the same time!
I hope that you have a wonderful time this November, full of Disney magic and memories!
Let us know if you have any more questions...We Disney Moms & Dads are here for you!