Crookneck squash are of the soft shelled or summer squash variety. Soft summer type squash are picked when somewhat immature, with seeds small to non-existence. When purchasing Crookneck squash, look for squash with a nice lemon yellow color,  4" to 6" long squash that are heavy for their size. The rind should be tender  and smooth. There should be no bruises or soft spots. The flesh should be light yellow to cream  in color and is loaded with Vitamin C. Crookneck squash is low in calories at 25 calories per cup served. All squash is loaded with fiber.

Crookneck squash should be stored in cool dry areas of the storeroom, 42 to 48 degrees F. best with 70 to 75% humidity. 

Here is a list of Yellow Crookneck squash recipes and other squash information"

http://dansgardenshop.com/gardenshop/golcrooksqua.html

http://www.humeseeds.com/sqshcnk.htm

http://mucus.com/recipes/stuffed_yellow_crookneck_squash.html