Noob here.
If I have bitcoins in a specific bitcoin client wallet (e.g. Amor, or Multibit HD, etc) and for some reason that wallet and its associated software client on my phone or pc no longer works (perhaps no longer supported by the operating system-- I have seen that happen with games, e.g. Diablo I, Diablo II games would not run on Windows 7), how would I get my bitcoin money? I don't understand if a bitcoin wallet from one specific software client is portable for importing into a different software client. Of course one should backup one's wallet, but that won't do any good if the software client that creates the backup does so in its proprietary data file format. Cold storage is one option I suppose, would that work, but still what if one did not want cold storage and its theft risks? Confused, and this seems important to me at least, so i know I would not lose my $ because of software no longer working.
you don't have to worry about this. you just need your wallet.dat and private key
wallet.dat file is compatible for any operating system. and for private key is your backup if you need to move your bitcoin into another wallet
just need to export your private key from your wallet and then import your private key to another wallet