Sit as far forward as you can afford. That's why the 2 winged master race are always at the front!
We sit up front because that's where the paycheck is.
I don't think there's anywhere on the airplane that's more comfortable so far as the ride goes, though the business class/first class seats tend to be a little more comfy.
Personally, if I'm not driving you'll usually find me somewhere as far toward the back as I can get, asleep. It's closer to the restrooms, and closer to the galley.
Anywhere aft of the engines will be louder.
Anywhere nearest the center of gravity will have the least movement. If you figure out where that is, let me know. I might move there.