Yup, Reston is a great place to raise kids with all of the connecting paved walking\bike trials(connecting to the W&O trial), tennis courts, community pools\waterparks, golf courses, and RHOA sponsored Summer camp activities. Lots of Lakes for fun.
The Reston Town Center, Lake Anne and soon Reston will have a Metro link so you can work and visit DC without the hassle of DC traffic.
Don't forget to check out the kayaking classes on the Lakes.
Check out the Reston Homeowners Association site for more details of parks and activities.
http://www.reston.org/index.html
Sweet!