There are 2 big estates in Kingston; Cambridge Estate (in Norbiton, just outside the town centre) and Kings Nympton, up Kingston Hill.
Both of these estates although not without their problems, have plenty of nice, houses on the outside. (Meaning 4 bed victorian town house type houses) So, its hard to say they are 'bad' when 5 mins walk away there are some gorgeous family homes, and the local schools (seniors particularly) are made up of a mix of children from both areas.
There is another estate, Alpha Road estate in Surbiton, but again, its bordered by some lovely areas (Berrylands) and not really considered a problem area.
One of the best primary schools in the area (have no idea if it still is) was Coombe Hill Primary. Coombe Hills is one of the more expensive areas of Kingston (its on the New Malden side).
Villiagey/Safe roads are difficult to define. Its fundamentally a commuter belt suburb.
As has been mentioned Surbiton is nice (20 years ago I never thought I would say that!)
My sister lives in Thames Ditton which is officially classed as a village, has period homes, gastro pubs, independant local shops. Is a 20-30 minute walk into Kingston town centre. Is still on the main line to Waterloo.
I think you are better off looking outside of Kingston town centre.
Hinchley Wood, Esher, parts of New Malden, Surbiton, even Tolworth, Thames Ditton, Long Ditton, Berrylands, Ham, Hampton Hill, Hampton Wick these are all nice areas to live, and to bring up children in. Obviously there are nasty bits to every area, but the nasty areas here are still not too bad.
Norbiton, which I have mentioned, has its own station, but is a stones throw from the town centre (& Tiffin Boys & Kingston Grammer, if thats important to you) its not too far from Richmond Park either.
Does that help?