How funny - was about to recommend our village of Goring, only to see someone had got there first (Lily - are you from there??)
I think it meets all your criteria brilliantly, thought it isn't cheap. 800 will get you a nice family house with a decent garden, but nothing spectacular.
We both work in Oxford and visited a dozen villages before settling on Goring, but more people go towards London for work. Most people move here after working in London -usually when their children are toddlers - so there is no 'outsider' thing at all. But then people stay forever, so it's a stable community too. There's a good village primary that almost everyone goes to and it's at the heart of the community. Streatley (on the other side of the river) is a bit more hot-housey. It's undeniably middle-class, but I've never found it competitive like I hear from some Oxford/London schools or on here. Then most people take the school bus to the 'outstanding' comprehensive school in the next village (Langtree).
Plenty of local shops etc (grocery, convenience stores, hardware, chemist, butcher, florist, medical centre, library, toy-shop, office-supplies, interiors, bric-a-brac, hairdressers, bike shop...) but no supermarket. It's definitely a village. Four pubs, fabulous cafe, tea-shop, posh restaurant, Indian, Chinese...). Supermarkets are 10 minutes drive. Delivery no problem.
Trains: 1 hour london, half an hour Oxford, 10-15 mins Reading.
Very active community. South of England village of the year last year. Xmas eve torchlight procession, regatta, lots of sports events, jazz festival...
Very outdoorsy, sporty place. You've got the river and the Chilterns. Lots of people cycle, run, row.
I think it's pretty relaxed - lots of festival goers and camping. Definitely a 'yurt' kind of place!
Everyone I know here is very glad they chose it. I'm not sure quite sure how it'll be with teenagers (certainly could be worse as transport is good) and I wouldn't move here as a single twenty something, but with young children (or retired) it is fab.
Have I sold it yet?