Banyan Bay has 2 bedroom suites so it may seem a bit big if you are traveling alone (and is double the price).
We just got back from Banana and really enjoyed it. They are one bedroom suites. The bar next door serves the best Mata Coladas (a pina colada with amaretto and bailey's added).
Banyan has a nice pool and a nice bar that serves food.
Both are a ways from town from 1.25 miles for Banyan and 1.5 miles from Banana. The market is about 3/4 of a mile away.
As a women I wouldn't really walk around any country alone at night, I just don't think it is smart. I always felt safe walking with my husband though.
If you are traveling during the low season (now) you might want to just book a few nights and consider changing accomodations when you get there. It seemed that there are better "walk-in" rates so you might even get a good deal. A lot of people seemed to be doing this. Have fun.-nat