Custard - Go to downloads.com(download for free) and look for 'vlc player' the symbol is an orange traffic cone( i dunno ),its prob the best player on the market at the mo , it plays virtually everything, highlight the film, right click,open with vlc player-job done,enjoy.
If you want to put the dvd onto a disc id recommend Nero v 7 or 8 - what torrent site did you use as theres a few i can recommend that are quite safe,stay away from limewire,kazzarr tho-laodsa viruses.
Hope this helps
Joker