If you have kids, the Peach Tree City schools are rated excellent as far as the south side goes. However, Marietta has some excellent schools as well along with Alpharetta and Roswell.
I lived in Newnan for a year and I would say it wasn't bad. After a high school girl was shot and killed in our apartment complex, we decided to get out of Dodge and buy a house on the northside. Lived in Woodstock for 2 years. All said, my wife and I liked the north side much better. It really depends on what you are looking for. In general:
Northside is a lot busier, many nice suburbs to chose from, closer to the lakes and mountains, many indoor malls if your wife likes that(mine does). I cannot think of one big indoor mall on the southside. Doesn't have the same "Southern feel" that you'll get from driving around downtown Newnan.
However, I would agree, avoid having to use Georgia 400 to get to work. Traffic is busier and it takes more time to get to the parking lot. I drove 45 miles to the employee parking lot, and 85% of the time it took under an hour. In traffic at rush hour plan on doubling you normal drive time. I used to bid for late show trips, where you would start later around noon or so and finish later, 8pm or so. This way, traffic is rarely an issue. If you like the early morning stuff, go with the southside to avoid the headache of the highways.
Southside is for you if you don't want to be bothered with a long drive home from the lot. It is cheaper as well, but I found Woodstock to be priced comparably to Newnan. Peach Tree City is the higher priced suburb on the southside.
I believe before you do anything, simply rent a car for a day and drive down to Newnan, take highway 34 toward Peach Tree City and Fayetteville. Then check out the northside like Alpharetta, Marietta, Sandy Springs, Woodstock, Roswell, Kennesaw, etc. Good luck.
