I've never met a truly bad cookie, so if you're lucky enough to sample a "gourmet" cookie I wouldn't hesitate. Of course this should take any food allergies (such as nuts) and personal preference into consideration. If I had to pick one cookie I'd go with the classic tongue-tempter -- chocolate chip.
Popular opinion says Mrs Field's chocolate chip cookies are the best. According to the sales, these cookies are the most bought. Mrs Fields now makes up cooky gift baskets with chocolate chip and other wonderful treats.