Hi,
Accomodation is a tricky one in AD, there is not much around.
As a new joiner you'd have the option of a villa (typically 3 bedroom) or an apartment. Four bedroom apartments are entitiled if you have 3 or more kids.
When and where the accomodation happens is pure chance at the moment. You won't have a good idea of what is available until the day before they offer you something. Ask to see some accom during the interviews, not normally a problem for them.
In general though, the accomodation is fine ( when you have some). Plenty of room and lots of other expats in the vicintiy. The wife and kids will easily fall into some support group or other. Typically set up around sports or school activities there are many great night outs to be had with friends.
Check out the Abu Dhabi mums website or you might want to join a club, the British club downtown has lots going on.
Good luck