It seems like those pictures would fit well over those chairs and the table, but you're not showing the whole wall in your picture so I'm not sure whether this will also cause them to be centered on this wall. Cut and tape some printer paper together to replicate the size of the prints and then tape them to the wall with painters tape to see how they look. This way you can move them around and try different arrangments before hammering in a picture hook. Once you get something you think is right, if you're still not sure, you can add a picture of it to this post for opinions. If they are a set you shouldn't hang them too far apart from each other. They should only be one to two inches apart. Usually if they're further apart the arrangement loses cohesion. Usually art is hung at eye level, but sometimes when hanging above a seating arrangement it is better to hang them lower than that. You don't want them to look like they're adrift on the wall, unrelated to the chairs.
Q