Please Help! My computer wont play or copy mini dvds

hello out there! can anyone help - i bought a sony handycam that records onto mini dvd disks but i cant play them. windows media player says
''Windows Media Player cannot play DVD video. Open Display in Control Panel, and then lower your screen resolution and color quality settings. To view the DVD Troubleshooter, click More Information.''
which i do but it doesn't help and none of the troubleshooting helps.

on other occasions when ive tried to copy the mini disk onto dvd using Nero it tells me that it it is not a dvd compatible file type .

i'm going nuts 'cause i really want to get the files onto windows movie maker so i can edit and what not.
pleesh to ghelp meee!