Hi if it is a real private key then it should start with the number 5, letter k or L. Go to website
www.electrum.org and download wallet. When youve installed then click wallet tab then private keys. Then you can import your key there. It will show your coin.
This is
not going to work. The OP has a bitcoin core wallet, not an Electrum wallet. They both use completely different file formats for storing the wallet.
Anyway, if you get "some private keys decrypt but not all", that means your wallet is corrupt. Did you try running:
./pywallet.py --recover --recov_device /path/to/wallet.dat --recov_size 1Gio --recov_outputdir /tmp/pywallet-output
And then check if your private keys are located in the /tmp/pywallet-output folder? It's your best shot at recovering them. You may have to change /tmp/pywallet-output to a different folder if you are using Windows.