Need help in buying a puppy

Hello Sachin and welcome to myLot. I don't know about the breeds of dogs available in India but I think that there are some general rules applicable in any country. If you want to buy a puppy with pedigree and having his parents medical tested for the most common diseases, you must be prepared to pay more. All those medical tests and conformation shows cost, and a responsible breeder will charge you for this. Even if you buy such a puppy, nothing will guarantee the health of the dog, as genetics can play tricks sometimes. For example you can buy a puppy comming from two parents displasya free, and the pup can have a form of displasya. About the breed you should look for, you should better try a dog breed selector. There are plenty on the Internet. There are other things you may want to consider beside the size and coat color. Here's a dog breed selector from Dyscovery.com: http://animal.discovery.com/breedselector/dogselector.do