I had some BTC in an ancient unencrypted wallet I've had since ever. I migrated to a client with an encrypted wallet later, however I forgot to delete the unencrypted wallet from my uber-old computer I use to pay the taxes. Now I have reason to believe that the unencrypted wallet may have been compromised, fortunately to a person who doesn't know what Bitcoin is. Still, I'd like to be on the safe side. Since then I have made numerous additional addresses and made numerous payments using my new client. Is there any way of checking the 'balance' of the addresses that may have been compromised? Also, can I use a bitcoind-style 'move' command to move the funds to an account not controlling that address, or does electrum even use 'accounts?' Or would it be best to just make a new address, and transfer my entire wallet balance to that address?
Basically I'm not entirely sure how the internal distribution of money works within a wallet to the addresses within that wallet. Could somebody explain it to me, or help me fix this problem?
Thanks