Head to south goa and look for Cola beach, agonda, patnem, galgibaga and arambol. There are many under explored beaches. Most tourists don't wander but it's worth the effort.
Hi Suhail, It can turn out to the travel experience for you with relaxing beached and laid back attitude. Here is a curated trip by travelers on Tripoto that can help you plan your trip better. Please check it out.
You can take a day trip to dudhsagar now that the trains will officially halt at dudhsagar for tourist,
then you can check out Salaulim Dam and botanical gardens the next day ideal for family outing.
keep one day to relax on the Beaches of colva or benalium if not a beach person den u can also check out Cabo de Rama fort as well (there is no climbing as such can be visited with family).