France. Both are good, but northern France in particular has a very similar feel to the south of England. If you want mountains, there is a plethora of resorts in the Alps or non resort towns and villages nearby where there are a range of affordable properties.
The not driving bit makes a huge difference. The point of retiring to France is to be in the countryside, which means little or no public transport. In Spain, people tend to retire to seaside resorts where you don't need a car. You can of course retire to a seaside resort in France but I just don't see that many Brits in Deauville or Le Touquet!
I've bought a retirement home in France and currently use it as a holiday home. The neighbours are friendly, the rural area is well run and its bliss really. There are many, many Brits here but they tend to be more integrated and less living the expat life. Ironically I was put off buying in my own country, Scotland, due to the unstable political situation and growing resentment of second home owners, plus the extra stamp duty and council tax. In France, the council tax equivalent is around 20% of what it would be for a similar second home in Scotland.
In France, you are also very central to the rest of Europe, if you want to drive to Scandinavia for your summer holiday, or get the boat back to the UK for some shopping. But Spain is lovely too.