Latin to English Art/Literary Linguistics

Hello,
I am spreading the net wide with this question that I have already asked in Latin to French
I have just finished the Fr/En translation of the Beaujeu audioguide. In the text the authors state that the name of the town originates from the Latin « bello joco », which, for them, means beautiful moutain. Even with my limited, failed O level Latin, I have doubts. To me it means something closer to the name of the town itself, coming out something like handsome game... Maybe a with a meaning differing from what we understand today.
I'm asking, to be able to give informed arguments to the people I''ve done the translation for. I'm a bit of a nit-picker and can't abide to give things in wrong, even if it isn't my fault. Of course, the info will be very useful for my personal 'furtherment' if my doubts aren't founded.