Electrum is a desktop wallet (best download it from there site: electrum.org) so keep in mind that you do it on a computer, on which only you have access to. Once installed make a new wallet and then import the private keys. Sweeping (transferring all your funds to a new address) would be safer, but you would have to pay transaction fees. You should now be able to see if your funds match. Before sending funds make sure to understand how to pick a proper fee.