Moving to DC and need advice on preschool/pre-K and neighborhoods. What do you recommend and why?

My husband just accepted a position near the Tenleytown/AU stop on the Red Line. We will be moving from Seattle to DC in July and need to quickly find both a family-friendly neighborhood to live in (preferably walkable, with access to a park, organic grocery), and a preschool or pre-K for our 4 1/2 year old son. He has been in the same Japanese immersion program since 9 months. We are hoping to find a place for him where he can stay through kindergarten and possibly longer. Are there any public schools you recommend w/preschool/pre-K? Which ones and why? Or, we're open to private if it's worth the cost. Any advice is welcome! Also, are there any Japanese immersion programs during the school day or outside of it?
Thanks!