Medieval Total War - cant play campaign mode

[bluenautica13]

i am having this problem with the game Medieval total war... i can play the battle tutorial and the quick battle modes but for some reason when i try to play the campaign mode or single mode it doesnt let me.. it just keeps going back to the menu... i am running windows xp and i have ati all in wonder 32mb video ram.. maybe i just have the wrong crack.. i dunno.. i have to find out.. i really like this game... thanx