Hi - I found everybody's advice really useful before we went on our trip to DLP over half term so I thought I'd feedback on what we did and found useful - mainly cost saving things.
We stayed at a Citea apartment at Magny le Hongre just off the DLP site. I appreciate that there is no Disneyland magic there, and that if that is what you are looking for then you are best to go to the Disney hotels as this is not Disney and is completely characterless - but was clean, fairly spacious and had fully equipped kitchenette and satelite TV. Two spacious bedrooms (double & twin) and a put-u-up in the lounge so would sleep 5 or 6. It cost 110 euros per night.
We were surprised at how far away a lot of the Disney hotels were from the theme parks - and our apartment was really just as near. There was a bus from directly outside which went to the parks, and you would have to get a bus from the Disney hotels anyway unless you wanted a very long walk.
We took our own car (Dover -Calais ferry £66 for car plus passengers) and food with us for breakfasts and easy pasta meals in the evening.
The food in DLP is very expensive (fast food places are 13 euros a meal for adults, 6 euros for children, and the all you can eat buffet in the studio park, where the food was actually really nice cost us nearly 70 euros for 3 of us. So, if you are trying to keep costs down and are self catering like we were, then take your own food in with you.
We were warned that you are not supposed to do this, and that people search your bags. However, they really are searching for bombs not for sandwiches/apples/water bottles, and there are seats/walls where you can sit down and eat within the parks. I saw plenty of people eating their own stuff and nobody being told off.
If you are taking your car right to the parks rather than using the bus, then park in the Disney Villages car park, not the Parks car park as this is a lot nearer and costs the same.
There are lots and lots of shops offering expensive Disney merchandise - we went the week before DS's bithday and told him he could have £50 towards his birthday present to spend either in the Disney shops or when he got home. I have never seen a child so choosy about what he bought!
Hope some of the above is useful to somebody!