Of course you'd be better off turning those Lawns into Gardens (in my humble opinion) but if you must retain some turf, try a manual reel mower. They're cheap, use no fuel other than a little of your love handles, have no emissions, and are relatively easy to sharpen. I just sharpened mine so I'm not just tossing out web links here.
But if you or your neighbors do bag up all those leaves and grass clippings, consider this a prime time to start a compost pile. There's a more in-depth article on why and how to compost here, but if you're looking for a more simple explanation of how you can recycle your yard waste and create some great compost for your garden, here are some simple directions.
Step One: Gather leaves and grass clippings. You may have some from your own yard or you might notice neighbors hauling them out to the curb. I went a step further and found a pickup truck load of bagged leaves and grass clippings within a mile of my home last Sunday afternoon.
Step Two: Pile up your material, alternating between layers of leaves and layers of grass clippings. A good ratio of leaves to grass is about 25:1 so you'll want to add more leaves. You're hoping for a pile about 3' X 3' X 3'. [Warning, horribly over exposed photos coming up.]
Step Three: Add water. This is best accomplished as you layer your pile. You want enough water to saturate your material but not so much that you pile is sopping wet. That will keep out oxygen, killing the beneficial bacteria ready to work for you. You can add other stuff too like saw dust or kitchen scraps, but grass and leaves will make fine compost all by themselves.
Step Four: Wait. Your pile will heat up over the next few days. As it cools down (anywhere from 10 days to 3 weeks) turn the pile, which just means mixing it up to add more oxygen. This isn't absolutely necessary but it will speed up the process.
That's it. The pile will take more time still to completely break down into compost. How long will vary depending on the makeup of your pile and whether or not you turn it again. Be sure to add water if regular rain doesn't.
Feel good about keeping your yard waste out of the landfill and look forward to having compost to use in your summer and fall gardens.