Berlin has high crime in some areas- high drug and alcohol abuse, high domestic abuse, and a large amount of other crimes. Cost of living is quite high (not low) because there is no business competition. Get used to shopping at the very small local WalMart, which is nothing like most Wal Marts. The cost of most items is very high- used cars are extremely high because they don't last long (At 10 years old, many are in the junk yard from rust), auto repairs are frequent and expensive (rusted lines, rusted fuel tanks, rusted brake components, rusted floors...you get the idea), and general household supplies are high. We don't have any chain stores like Circuit City, or discount places like Sam's Club. We usually try to make a trip to Concord every few weeks to stock up on supplies at Sam's Club. Even with the high gas prices, we save a ton of money over the local stores.
If you want northern N.H., stick a little further south, like the Plymouth area. Its still rural, yet close enough to Tilton and Concord to stock up on supplies without spending a whole day out of town. There are also rural towns not too far from Concord that give the country life without being in a wasteland like Berlin.
The problem with most of the towns mentioned in other posts is that they all rely on Berlin for shopping or employment. Littleton is getting better, and is far enough from Berlin that its not affected by the Berlin problems very much. Employment is getting better, with more businesses opening up. Berlin, on the other hand, is a dieing city. If I hadn't gotten married while here, and now have my wife's family up here, I'd be gone in a heartbeat.