Playing Videos On Bush mp4?

I brought a Bush 8gb Mp3/4 player for the first time and loaded all the relavant software on the disc that came with it to it but I am having problems getting films to run on it.
I used the Fab Platinum ripper to convert the film to an mp4 file and then drag and drop it over to the mp4 . I am then informed that I could load it to the player where it would be stored but will not play.
Not being tech minded am I missing something here as I can see the file on the mp4 screen but I canot get it to play.
Do I require some extra software to start it ? Any help most appreciated