Okw is big enough - there is only one crib in the bedroom (it will be in a closet) so you will need to call housekeeping to bring you another.
Okw has a king bed in the master and a queen sleeper sofa in the livingroom - it also has a love seat probably big enough for one of your children - but you must bring the extra sheets and blankets that your child will need.
since you have 2 children under the age of 3 - I don't think you will have problems.
now when you children are over the age of 3 - then you might need to consider a 2-bedroom. (for your sanity if nothing else)
now this is only true at OKW - the other DVC resorts even in a 1-bedroom you will be crowded.