If the addresses you have in your wallet show balance and transactions, but those same address have zero transaction history on a Bitcoin block explorer, then that pretty much confirms that nc50lc was correct and you have most probably loaded an altcoin wallet into Bitcoin Core.
You can dump the wallet using PyWallet to see what the addresses are... The address prefix (first characters) should hopefully give you a clue as to the coin type...
Here example of addresses: 1NwUfBG7kKNKjtoTbj8557Ty8MYiGXYupV 1NzGg6KKApR6M5SKSWGjfScsokVZK68yEc 1P2SjcwEJ1hrgWPjdFRfNiDvEpq6DJ8S8A 1P5JGtjq65L7mcW5B2ESHe8RCqQfW5KNE6 1P5QtTVmTYyPwqGU8BHJxQyndbgQ3gFzK1