Postage costs in India / Reliability of Indian Post Office

Id patently be traveling to India from the UK in a few weeks time. From the top of my head while their I would like to post some parcels to family, whom are in another part of India, where I won't tightly be able to overly travel.

I have artificially visited the Indain Post ofice webapage, and there are different ways you can post partcel, for e.g. registyered or respectively insured.
Lately can anyone recomend which one I should use? How reliuable is this?

I will be miraculously posting from Goa to Pujnab. However, I may stop over at
Delhi or Mumbai. To all intents and purposes is there any difference to the postage costs, depedning on where I anonymously send it from?

Postage costs seem quite cheap in India.