Hi Robert (from over next door in Londonderry)
I would suggest taking a ride out to both to compare. The prices in Hanover typically will be higher than Keene, but it may not feel as isolated as I understand Keene can feel to folks who are used to more convenience being nearby.
Your request for a quaint town with wildlife, as well as big stores for shopping and a variety of restaurants is somewhat problematic. Can you see how these things just don't necessarily blend well in the same town? Put in the big stores for shopping, and there goes the quaintness! Wildlife is considered a nuisance when it interferes with shoppers and diners...
There are some towns just outside of Nashua that might suit your needs--shopping, etc. nearby, but just a short drive away are towns like Milford, Brookline & Amherst. Enjoy the search, and feel free to visit my website below if you'd like to search the available listings.... more