We've recently used les castels sites in France which we've found great for kids; the facilities are generally very good and the sites are not too huge. My feeling with small children has always been to avoid sites that are really big and that have massive water-parks, as these tend to be more appealing to families with teenagers; visions of small dcs getting knocked over in the rush for the pool. I take the view that a smaller site with a pool and maybe a slide or lazy river is enough - we'll go to the big sites once the dcs are older.
Forgot to say, it was quite a drive down but easily manageable. When we go back next year we will pay the extra to get a longer ferry crossing and reduce the driving distance in France. However the roads are much better in France than here. Would definitely recommend getting cabins on the ferry if you have a night crossing.
We stayed here last summer and had a fab time. Its a really friendly site with a mix of English, French, Dutch and German families. We took our own tent but they have tents and mobile homes to rent on site.
The facilities were really clean and the kids loved the pool, play area and bouncy castle. There is a nice bar on site and also a shop, though we mostly used the shops in the local village.
There is a beach within walking distance but we didn't use it as we like to go further afield. We did have a look and it looked lovely and clean.
Have a look on UK campsite as it has some lovely reviews on there.
We have never been abroad with the dcs before, and have a 6 year old, a 4 year old, a 2 year old and a 3 month old. We thought we could try staying in a mobile home and have been looking at Keycamp/Eurocamp etc, and got a brochure from Yelloh Village (sp) but literally don't know where to start. I don't think we need a huge parc with lots of pools/chutes etc, but near a beach might be a plus. We generally like it fairly quiet with nice scenery, but not against trying something new, and realise that the more there is for the children the better it might be all round! At first was thinking don't want to have to travel too far from the port(s) but again open to suggestions. Which parcs do you love and why? And do you have a recommendation about which company to go with? Thank you, I'm looking forward to hearing your ideas.