How to choose: Look for pods that are firm and crisp. They shouldn't bend at all but should snap. The color in general should be a saturated pale green. Some peas will show a little white scarring on the pod; that's not a problem.
How to store: Refrigerate in a tightly sealed plastic bag. They'll last four or five days.
How to prepare: Many sugar snap varieties have a tough fibrous string that runs the length of the pea and should be removed before cooking. Fold back the stem and pull -- the string will unzip quite easily. Check carefully; some varieties have strings on both sides (just repeat the stem operation from the opposite end). Cook sugar snaps very briefly to preserve their flavor and crunch.
Here's one great dish: Chop some chives and shallots and stir them into prepared mayonnaise. Combine cooked, shelled shrimp in a bowl with a couple handfuls of sugar snaps, and stir in just enough of the mayonnaise to lightly bind them. That's dinner.