Vista - Medieval 2 total war gold edition and vista

I have just bought Medieval 2 gold edition and am having problems getting it
to run.
all goes fine till the game tries to load.The intro is perfect but as the
game is about to start i get an error message:unspecified error windows will
now close then the game screen goes blank and the timer keeps turning and i
have to use control,alt ,del.
Please can anyone help i've tried a lot of forums but can't get an answer
that i understand.
Thanks