Self catering preferable.
Bourg st maurice is nice.
plenty to do in the valley for the family and just a little bit of riding for you.
also la tania is nice near courcheval, nice outdoor pool.
If your family is very young and hence you want your alps a bit smaller than usual, then I can recommend Kitzbuhel. I went with my wife and 10 month old and some MTBing buddies. It was a walking holiday with biking. The walking is mostly unthreatening with cable car access to the top of the main peaks, but they'll take up bikes too.
When I was there in 2007 there wasn't much in the way of waymarked biking but we still had some great rides, albeit we were glad of a guide. The best thing about Kitzbuhel is not the biking - there are far better resorts if you want an all out biking holiday - but it is a pretty town of a good size with lots of other family-friendly stuff to see and do.