Since bluray drives can read DVDs, DVD are not going the way of the dodo anytime soon. If you can afford it and willing to spend quite a sum ( this is a very expensive hobby), bluray Is the way to go. The extra details of bluray are such that once you get accustomed to the finer details, it's hard to look at DVDs. But you might want to buy DVDs for those lesser titles, since DVDs cost a fraction of bluray, especially on locally available catalogue titles.
That said, but aware that go into this hobby only if you have money to spare because eventually even bluray will be superseded by newer technologies, look at beta, VHS, laserdiscs (or lp, cassettes,CDs). So your collection will decrease in value over time.
Then if you get into it, make the most of it - enjoy the movies. Only then would you recoup your investment.
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