Welcome - you have found the right place!
If you are interested in DCGS you need to move into catchment quickly or it's unikely you'll get a place; they have their own rules about how long you need to live locally.http://www.buckscc.gov.uk/bcc/schools/admissions/school_admissions.page?
is the place to start to find catchments etc. Good primary schools will tend to be full ...
I would think about Secondaries first - the 11+ is changing too - see sticky and panics from posters!
Everyone has their own preferences - do watch out for the proposed HS2 route so you don't live next door to it.