You should not use an outdated version of Electrum. You will have problems sending and fee estimates will be too low. Newest is 2.8.3 at Electrum.org. Electrum explains how to use two computers (one always offline) for cold storage here. Almost no one bothers with this setup anymore since hardware wallets are more secure and inexpensive. Get a hardware wallet.I agree. These are your best bet to guard against any attack you don't want. Having hardware wallets don't share what they have inside. So even if you use them on a virus infested computer you have, it will still store your coins safely.