Bitcoin-Qt and MultiBit do not use the same wallet files. You cannot import the wallet.dat file from Bitcoin-Qt into wallet.dat.
If you still have the Bitcoin-Qt program running, you can export the private keys from the wallet. Then once you have the private keys, you can import their values into MultiBit.
Exporting private keys from Bitcoin-Qt is not part of the user functionality. You will need to either use server mode or the Console in the Debug Window to issue API calls. Here is information about the available API calls that you can make:
https://en.bitcoin.it/wiki/Original_Bitcoin_client/API_calls_listThanks! Im half way there, I have my private key copied and pasted into a open office folder. Now I have to import this somehow into my multibit wallet. Im busy looking for an easy way to do this, but I cannot find one....