Hi Sandra,
Agree with the other postings, the cities of Gent and Brugge are just great.
North of the French / Belgian border at Veurne, is the Dutch (Vlaams) speaking region of Belgium. Don't try to speak French in the shops, pubs or restaurants - likewise speaking Vlaams in the Southern part of Belgium.
Bruges is called Brugge (pronounced like the second part of Zeebrugge).
Certainly recommend getting a campsite close to Brugge so you can spend a day or so looking around the city - park in the big car park South of the city and walk in. It is just so pretty, great food and even better beer.
If you want something with a beach, then I'd probably head North of the Westerschelde estuary - about 30km North of Brugge, head into Southern Holland and pitch somewhere near Middelburg - the large beach at Vrouwenpolder is big - lots of quality campsites.
I would probably avoid the Belgian campsites on the coast around Nieuwpoort - again there are lots - but the pitches are smaller than the sites inland or in Holland.
Get a copy of the Caravan Club or Alan Rogers guide and have a read over Christmas.
If you need any help translating Dutch into English, just ask (robert.jackson@eriba-amiga.co.uk)
Robert