UPDATE: The instructions above will still work with the latest Qtum wallet (i.e. Ignition v1.0.2).

I should also mention that if you restore your wallet.dat file, you can opt to restart qtum-qt (or qtumd) with the -rescan option:

  -rescan
       Rescan the block chain for missing wallet transactions on startup

This will ensure that your wallet/node knows about the UTXOs from your restored wallet.dat file. In theory, the wallet should do this automatically, but it doesn't hurt to force it.