Hi Michael,
You won't need a license to import DVDs. Your main concerns will be whether the DVDs are legitimate region 4 (pretty unlikely from China unfortunately) and the import duty.
You can take a look at information on duties here: Link hidden: Login to view
But you'll save yourself a lot of time if you just email or call customs and ask them to tell you. It can be tricky working out exactly what duties apply when you you're inexperienced.
Customs Information and Support Centre (CISC): telephone number 1300 363 263 or email: information@customs.gov.au