Not Eurocamp, but I take my kids camping here every summer. We actually live under 2 hours from there (in the French Alps), but my kids love it there and demand we go back every year, no matter what other destinations I suggest!
Prices are very reasonable, they have a kids' club in the summer and lots of activities in the evening for families etc. A good mix of nationalities (lots of Dutch, who generally speak good English). We French are often a minority, which means my kids get to practise their English :)
If you book long enough in advance, you should have a choice of chalet, caravan or tent pitch (we bring our own tent and bikes, but I think you can rent both).
It's also a good base for days out if you're into that - you have Dijon/Nuits St George, Macon, Lyon, Geneva, Mulhouse... within a couple of hours' drive. It's also on a lake, so there are beaches, watersports, fishing, a water theme-park etc on-site! Definitely a great holiday!