IT IS SECRETIVE!!!!!!!!!! Ha ha - we dont want it turned into another South Africa, it is so un-touristy (is that even nearly a word????)
Ok - so answers to your questions:-
To be honest because it is such a "new" detsination after the war, it is best / easiest to book everything yourself - there are luckily (or unluckily depending on what you want!) no package holiday companies operating in Mozambique yet
As to how to get there - you cant fly directly from UK as no big airports in Mozambique, you can fly into South Africa and catch a smaller plane into Mozambique, although I would recommend flying to SA then hiring a car and driving down there, as you can take your own time and explore beaches etc. What I would say about that is definatly stick to the roads and beaches when driving as still a lot of land mines in fields etc!
The currency is the metica, which is weaker than the rand, I think the current exchange rate is about officially about 48 meticals to 1 gbp, although you can exhange money with people on the road just over the border, who will give you a much better exhange rate as so desperate to get their hands on forex
Best time to travel I would say is between August and October time, that was always my favourite time - any later than that is too hot, and also can get very humid, in this period you are looking at temperatures of about 30 - 35 degrees C which is not too bad
Kids will love it - the reason i have been here so much is I used to live in Zimbabwe so we went on family holidays to Mozambique, I first went there at 14 and have loved it since - the beaches are very clean, baeutiful clear water to snorkel in, not snorkeling like in Greece etc but stunning beautiful fish swimming around. If you make a decision on the area you want to go to etc then let me know / speak to someone who knows the area as you can quite often organise things like parasailing, deep sea fishing which is so exciting, or even just hiring a boat to go out to the islands and the coral gardens. The other side of Bazaruto island is a great white breeding ground, so very exciting for kids too!
Have a look here
http://www.vilanculos.co.za/gallery.htm some pictures of vilanculos where we are, a beautiful lodge that I have stayed in before
Anything else I can help with?