The War of Spanish Succession would definiely still happen here: the greatest fear of the other European Powers was France and Spain getting in a Personnal Union. The Duke of Burgundy was 2nd in line for the French throne, right behind his father Le Grand Dauphin. This basically meant that if things had gone normally, the Duke of Burgundy would eventually have become King of France. Thus, if he's crown King of Spain, you get the Personnal Union the other powers dreaded...
It's precisely the reason the Duke of Anjou was selected as the French candidate to the Spanish throne: he came after his elder brother and his sons, so chances for a personnal union had been weakened. Still didn't prevent the War of Spanish Succession, but at least the Sun King tried to reassure his neighbors on that point...