Leisure allows the brain to relax, or at least to have it switched into non-competitive mode.
Most of my Recreation and Entertainment activities were rather passive in nature, so I was happy to occasionally immerse in Car Control events.
I like board games, card games, puzzles, and mind sports in general, e.g. Settlers of Catan is a good example of a game I have been playing purely for fun. Also, Callisto is a very nice game, being immediately playable by anyone of any age. If you're into spatial problem solving (like e.g. Rubik's Cube), you might want to try out Sokoban. I have solved 20 different levels (through Java based software on my GSM), but I needed several attempts per level. You'll see why :-).