I admit I haven't read absolutely every post so forgive me if I'm repetitive. I can empathise - being a little antisocial myself. I do play Bridge, though - which entails using the brain cells in a social situation with no small talk! And one never stops learning with Bridge - no two games are the same. (I'm with you - I find small talk can be very boring!!Though I do like a good meaty gossip now and then!)
I'm a school governor of a primary school, and now also Director of an Academy Trust, which is made up of 2 primary schools, and takes up a lot of time. Most local authorities know of schools looking for governors, especially ones who will take the job seriously. If you do the job properly it entails reading lots of documents, training, meetings and school visits. Governors who are working may find it hard to do all that is required ideally, so a retired person who will put in the effort is usually very welcome. It can be quite pressurised at times, as the Government seem to have put more and more responsibility onto Governors, and there's no pay! However, its intellectually challenging and rewarding to be doing something worthwhile; its also quite nice to relive one's early parenting days, and be invited to Nativity plays, Christmas lunch and other activities.If it interests you I'm happy to answer any questions.
Good luck anyway.