We went to Longleat about 2 years ago. The food outlets are expensive and very average. It is definitely worth pre booking activities, once you know when you are going, go on the internet and organise what you want to do. Don't forget not everything is next to each other so leave yourself enough time to get from A to B. Your children are very small, the pool area is great there and you don't need to book that. But some nice pampering time maybe... Also the Longleat Safari park is RIGHT OUTSIDE the gate, literally. So you can 'leave the park' and visit, that went down very well with our children. And a brilliant pub is in the village 5minutes away from the park. Feel free to pm me if you want to know more.