For clients such as bittorrent-qt and Electrum, how do I back up my wallets so that even if each software was no longer supported in the future (eg dead servers), I could still access my BTC balance by entering the info into future, functional clients? I think this means I need to get the raw private keys, as opposed to just backing up app-specific files such as wallet.dat in bittorrent-qt, or the seed in Electrum, which seem like they wouldn't work outside of the app.

Every time I re-install Windows and the QT client, I have to re-download the entire block chain which takes a long time. Can I copy my existing block chain files so that I won't have to re-download the same parts over and over each time? If so, is there a tutorial on the subject, or is it just a matter of moving files in and out of the installed directory, eg. C:\Users\USERNAME\AppData\Roaming\Bitcoin?

I haven't used my wallet for a month and today I tried updating the client and moved my program folder from c: to a different drive. Afterwards, my wallet's balance is remaining unconfirmed, even though bitcoin-qt says it's "up to date". I tried to update the balance by sending 0.01 BTC from another address to my wallet, but all it did was bumped my (confirmed) balance from 0.00 to 0.01.

What should I do to make it confirmed?

Edit: My transactions show up as unconfirmed. Only my latest test transaction is confirmed.