Get yourself a Gary Fisher 29 incher. You can fit a wide variety of tires for road and off-road riding or a combination of the two. You can fit it for comfort or for more aggressive riding. The disc brakes are pretty reliable under almost all types of conditions. The suspension fork makes it a little front-heavy, but it pretty much balances when you put a rear rack (after all, you're talking rides with your family right? where are you gonna put all those snacks and clothes changes, etc?). This is a good multi-purpose bike. It's rock solid and handles well. I own one and couldn't be happier with it. I do 50+ mile trips, every-day commuting, family rides. Again, a great value.
You will not look back.
GreenAnvil