Calangute Experience: Goa is great place to let go off your stress. No need of pills. :P
Food, sight-seeing and shopping: The traditional goan food is awesome. Other cuisines are average. Lots of eateries and street shops around.
Activities & things to do: You can hire a car or bike and explore Goa around. There are different churches, forts, beaches etc to explore. Water sports and night life is something to watch out for. Also, dinner at shacks in Baga is strongly recommended.
Travel tips, How to reach, travel warnings etc: If travellin by train get down at karmali. Hire a prepaid taxi.