The Leander School District is a great area to live with for the kiddos. They will basically receive a private school level education at a public school.
I live in Steiner Ranch which is a master planned community. It has elementary schools and a middle school. There are three community centers all with pools and parks. Steiner Ranch also has hike & bike trails, stores, "pocket" parks, lake access, etc.
Cedar Park is also a good place to live. Last year, it ranked #9 on the Family Circle list of the best place to raise a family. It is also in the Leander School District. There is a small subdivision in Cedar Park that is really nice and has great access to toll roads and major streets. Check out my website for more information at www.theKLMteam.com where you can find links to the Austin area school districts and to Steiner Ranch. The Market Snapshot can give you information on houses in specific neighborhoods.
Good Luck and Welcome to Austin!
L. McKinney