Both wires and cable can and should be good, in my opinion cable more reliably so. But only by making your own inquiries in your area you can get correct info. Of course, much will depend on prices, which again you will have to find out yourself.
I meant that it seems unsual to me to have 2Mbps on optical fiber (I would say "mini" 100Mbps, which corresponds to cable connection) but it may not be the same in India And with a 15ms ping, It seems quite high, and you may go down to around 5ms (1ms is the best though)
In France, with Orange ISP, only a single Optical Fiber ("fibre" in French) directly connects to the router (this is what I have) : https://img.igen.fr/2016/7/macgpic-1468241940-25780510601230-jpt.jpg Or we have this ONT : Spoiler It seems kinda weird in India but... it's India ;D
I don't understand :s I do think the optical fiber in India is swinging in the air (and apparently monkey are loving it so much they swing along it and eat it) so this may be one of the causes of latency/low bandwidth (in France, Optical Fiber is deployed through tubes under the road/sewer so there's no problem when there are earthquakes, floodings, .... animals ) In every country, a "cable" (copper, coaxial, fiber...) goes into the house (air or underground) and must be connected to a router (ISP, or public-one, Idk, depends on the country). Sometimes, it needs to use a block/filter (ADSL in France for example : http://portail.dartybox.com/cms/ima...1-3f52033815a4&groupId=805406&t=1348734761047 ) or an external device (Media Converter/ONT) or directly plugs in the router (like Orange ISP does in France with it's Livebox 4 Router). Coaxial doesn't need any of these (If I'm right) So much complicated...