I am dowloading movies off the Vuze.com site (ie 2012, avatar, etc.) and then upload to a dvd, but, my laptop "says" there is not enough space on my blank dvds, to burn. I'm using Sony 4.7GB 120 minutes. the movies are 2hrs 33min 45 sec in other words 153mins 45secs. How can I compress this time to fit the dvd?