Ryanair flys to Perpignan France from Belgium relatively cheap and my understanding is that is the point of entry to Andorra.
Any have any recommendations on family friendly places to stay and eat, and which mountain/resort(s) to ski at?
Andorra is not a pretty place. There are several small ski hills near Andorra like Font-Romeu,
Cauterets is a bit further west and has some more skiing with this being a good place to stay. http://www.hotel-du-pont-despagne.fr/
Bareges/La Mongie is now known as "Le Grand Tourmalet" is also further west and has even more skiing.