How much lawn? How much driveway? Hills? Flat? Pavement? Rocks? Gravel?
I bought a Craftsman. It's ok but I wish I went for the extra $$ to get the Garden Tractor vs the Lawn Tractor as it's got a heavier frame and is a bit more solid. All in all I do like it though I still have a fair amount of yard requiring a push mower due to some steep banks.
To mulch or not to mulch - I'm pro mulch and yes, I believe the mulching kits are a good investment. When you leave the clippings on the lawn they decompose and contribute to the quality of the soil and the health of your grass. Mulching blades are designed to break the clippings up into smaller pieces that will decompose more quickly and efficiently as well as spread them more evenly. IMO, get the bagging attachment as well. If the mowing gets away from you so that the grass is so long that you want to bag it you still have that option without changing your blades. Also, you can definitely use it to clean up leaves, etc like you mention.
Snow removal - I live in Vermont so there is no way in hell I would use my riding mower to plow. Maybe a larger one? Not sure... Between the chains and the available plow kit I'm already a portion of the way to a decent 2-stage blower. I also think the answer to this depends on your average snowfall. I had, if I remember correctly, 6 storms this winter with over 15" of snow (3 of these were over 20") and several more with 8-12". No way would a non 4-wheel drive vehicle be able to push that much snow around. If I rarely got snow or never more than a few inches I wouldn't plow it anyhow but, if I did, I suppose I could use my lawn tractor.
As for JD or some other manufacturer, I doubt you will find that much difference between them in similar price brackets. My mower was about the same price as the one you linked and the specs are pretty much the same. Between Craftsman, JD, and Toro you have some great options. I might stay away from Home Depot or Lowes versions of the JD though, they aren't the same as buying from a JD dealer. They are manufactured specifically for the box stores and with lesser quality parts so that they can be made and sold more cheaply.
The other great thing about a lawn tractor is the ability to get a small trailer for it for hauling stuff around. Even minor things like mulching or other basic yard work is made easier when you can pull a wagon behind you - not to mention how much fun it is for the kids

Hope this helps.
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