You don't ask for a translation of the third verse, but hey, on Mudcat we don't let that stop us!

Buvons bien, buvons mes amis,
Trinquons, buvons, vidons nos verres.
Buvons bien, buvons mes amis,
Trinquons, buvons, gaiement chantons.
En mangeant d'un gras jambon,
À ce flacon faisons la guerre!

Let us drink well, let us drink, my friends,
Let us toast (or click glasses), let us drink, let us empty our glasses
Let us drink well, let us drink, my friends
Let us toast (or click glasses), let us drink, let us sing merrily.
Whilst eating a fat ham,
Let us make war on this bottle.