Can those mini DVDs (used for DVD Camcorders) be inserted into the slot-loading optical drive of a MacBook Pro? Or any slot-loading optical drive for that matter?
There are CD/DVD adapter rings on the market, this is a problem with car players and the ancient CD caddies too. You're on your own to make sure the adapter you pick up is smooth and thin enough to help and not hurt the load/eject situation.
To the OP, the smaller DVDs cannot be used in a slot drive like used in the MB/MBP. My suggestion is to get a cheap external drawer type CD/DVD player. Simple and easy to use.