1) As far as Bitcoin is concerned I really doubt that there is any right time. Because it could happen that current price may be the lowest price or it could also happen that it may be the highest price.
2) I would say keep purchasing small qty at regular times. Afterall, if your from India still there is no clarity about Bitcoin currently.
3) Unocoin and BTCXINDIA are the most reliable at present. Service and quickness wise BTCXINDIA stands out among the rest.
4) If you would be purchasing smaller quantity you can store it among the blockchain itself. But once you have few BTC it is advisable to store it offline.

Also if you would like to buy/sell BTC you can contact me via PM or follow  https://bitcointalk.org/index.php?topic=837811.20

As long as more than 2 people agree on the Bitcoin protocol, Bitcoins price cannot go to 0. There are several other reasons as well as to why 0 may never happen with Bitcoin.

• This is impossible to answer as an investment, The Global market of Bitcoin promises that there will always be periods of highs and lows.
• It is always advisable to spread your buying rate around a long term average and follow that number.
• Reliability and Transparency wise, Coinsecure is a lot better than the rest. On Trade Order Book volumes seem low, but trades that come up at market price get completed very quickly.
• Depends on the volume of purchase, You could use an online wallet as a hot wallet, a Trezor as a warm wallet and a paper wallet that has your larger amounts.