Flat pedals with toe-clips (the strapless types). I find them extremely comfortable when set up correctly, and they keep my feet in the right position.

I am happy to accept that that clipless do provide advantages for many cyclists, especially racers, but I don't race or worry about increasing my speed, plus I often ride my bikes in "civilian" clothes so don't want to go to the unnecessary (to me, at least) expense of changing the pedals on a couple of my bikes and buying special shoes.