The cities are all mini-ghettoes or have mini-ghetto areas... Especially Bridgeport (Tha armpit of New England) as well as parts of Norwalk, Stratford and Stamford.
Depending upon where in Spouthern CT you will be, there are some towns which might make sense... Usually if schools are not a concern.
Fairfield County Towns that are liveable include:
Greenwich
Redding
Fairfield
Parts of Stamford and Norwalk
Monroe
Newtown
Easton
Weston
Westport
Trumbull
Milford (actually NH County)
Shelton & Long Hill
Stay away from:
Bridgeport
Parts of Stratford
Parts of Norwalk
Got something against Darien and New Canaan? ;-)