In a saucepan, bring the water, ginger, sugar, and lemon zest to a boil over medium-high heat. Add the pears, and when the pot returns to a boil, reduce the heat to medium-low to maintain the simmer. Cook the pears until very soft when pierced with a knife (but not falling apart), about 12 minutes.
Remove the pan from the heat. Using a slotted spoon, divide the pears among 4 dessert cups or ice cream dishes.
Add scoops of ice cream to the pears and garnish with a sprinkle of cinnamon, then tumble some fresh blueberries over each serving.