I mow my leaves and let 'em compost into the lawn.
Snakes: Not a fan of killing them, but not a fan of them near me and my loves ones. My philosophy is that all of God's creatures deserve my respect unless they decide that they want to move in. At that point they become vermin. If I can relocate them, no problem. If they are useless, i.e. mice, rats, wasps, ect, they get smited with majestic force and extreme prejudice by me. If they are squirrels that decide they like my attic, oh its on, and I get the fry pan ready.
Spiders get a heavy dose of 11D (my shoe size). Crickets too. I hate crickets, and they attract skunks and other critters.