i think in answer to the first question, it would have to be foursquare. my sister and i played that so much with all the other kids. besides, of course: tag (the many variations we had: bike, freeze, midnight, lazer, and so on and so forth), hide and seek, baseball (with a raquet ball) and butts up.
the answer to the second question would be (and this is going way back) my big wheel. oh, yeah. remember those? they were so fun. i could get a great slide going on with my e-brake. but i was a kid, so anything was "great".
so, what was yours . . . . ?