I think plenty of VNs have great stories, but if you're talking which medium is going to have more objectively better stuff then it's obviously books. Books are much, much more mainstream which means you'll have more talented writers writing books than VNs. But I think the main appeal of VNs is that the stories and settings are usually pretty unique to the medium (for better or worse).
As for the second question, it depends on what you've already read and what genres you're interested in. I don't want to give you some recommendation if it's a game you've already read.