I have bought my first place in Dorchester on Thames (Oxfordshire). I commute into London daily where I work and door to door is just over an hour which is great. It used to take me longer when I lived in central london just to get from east to west.
However, because it is easy to get into London, you pay a premium. again is very expensive, especially compared to Yorkshire (generally speaking). Oxfordshire is a gorgeous county, and being so close to London is a great bonus.
good luck with the hunt.