Emergency Preparation Gardening

That being said, I have a 'do-nothing' tree in my front yard.  I want to replace it with a walnut tree.  I will have the tree removed this fall, then:  #1-Can I plant the walnut in the same spot as the previous tree (centered in the middle of the lawn)? & #2-Can I plant my walnut immediately, or should I wait a year?

I know this has nothing to do with SFG, but it DOES have something to do with emergency prep gardening!  

I don't know the answers to your questions, but make sure your planned location for the walnut tree takes into account the negative effects of the chemicals that walnut trees produce. You'll want it away from your garden and you'll probably want to keep the leaves and husks/shells separate from your regular compost:
http://gardening.about.com/od/gardenproblems/a/What-Is-Allelopathy.htm
(/\ If you keep scrolling after you read that one, you should get to the next article "What Can't I Plant Under a Black Walnut")

Apologies if you already know about all that ...
My parents grew walnuts, but I don't think we ever ate any of them - no idea why...
I like walnuts on oatmeal, and in yogurt, with a spot of jam.

Also take care with how close you plant it to the dwelling .. they take a lot of water out the ground and have big root systems that can break into foul water pipe joints and cause you expensive repairs or refurbishment costs after land movement .

 Here in the UK the sellers of property are getting sale prices knocked  down by several thousands of pounds Sterling  if there is a water demanding or root invasive tree with in 60 to 100 feet of the dwelling or it's service or  waste ducts/ pipes .

Mellen, Have you looked at this thread? "Does anyone have any fruit trees?" Planting dwarf fruit trees instead of a walnut tree, especially, I think, a black walnut. I like the picture of the trees in a circle. Planting trees is something to research. Some, like Plantoid stated, have invasive roots, even cracking foundations. Your neighbor may regret removing most of the trees, especially on the west side where they can provide shade for the house. Shade on the west side might be helping keeping the electricity bill lower. I'm seriously thinking about dwarf cordon fruit trees: apricots, apples, pears, peaches and maybe a nectarine. https://www.growveg.com/guides/cordon-fruit-trees-how-to-get-the-best-harvest-from-a-small-garden/

PS I also bought the Vault series in 2012, and started some of the seeds. Then found this Forum in March 2013 and the rest is history. I still have so much to learn about actually growing and caring for the veggies.