So, If you have the wallet.dat file which is supposed to have your public and private keys etc ... you should be able to get your coins back by importing it here : https://blockchain.info/wallet/import-wallet
Make sure to send them to your Desktop wallet once you do that , because keeping your coins in a Online wallet for a long time isn't a good idea .
This should work since you mentioned that you have still have wallet.dat available.
It's crucial to make a proper backup of your wallet. If wallet.dat wasn't available, you would have totally lost control of your coins.
Wallet.dat isn't a proper backup.