Reseeding this fall... need help

ZONE - 7
Yard size - 15,000 sq ft

I just moved into a new house and the lawn is a mess. Crabgrass and weeds everywhere. The rest of the yard is fescue still mixed with weeds and crabgrass.

My plan is to attack it this fall with heavy aeration and overseeing of Kentucky Blue Grass. Is this a good idea?

What should i be doing now to prepare the soil for the new seed in fall? PH level is good (6.7)

Why not try some crimson clover? Around here, it starts flowering in February along with the henbit, and once the bees get used to coming for the clover, they are here when the fruit trees start flowering.

That wouldn't look very good. I want grass in my yard... Defiantly not looking to do anything besides grass.

Blue grasses are high maintenance, if that's what you want. Besides, it might not like the heat of your Sone unless you plan on adding a sprinkler and wasting your water on it.
I think looking for a no mowing low growing grass would give you the lawn you want unless you like adding to your workload.

Start any lawn renovation by getting rid of weeds, then choose your grass and follow the directions.

Rob - you are asking about lawn maintenance on a permaculture forum. The advice you get here will be geared toward unconventional lawns; ie low maintenance, mixed species, low input etc...

If you want a totally conventional lawn to mow and look like your neighbours you will probably need to look elsewhere.

Paul Wheaton's lawn care article