I'm not sure what you mean by "had ving." "Had having?" If so, it's grammatically incorrect. The first sentence is grammatically correct, but you would normally say "taking" guitar lessons, not "having."

hello, as you know the first sentence is in present perfect continuous and the second sentence is in present perfect .technically you can use both of them but first one which is in present perfect continuous shows that you're still having that guitar lesson it means that the action of having those lessons started in the past but you're still having those classes and it will probably continue in future . So if you want to emphasize that it is still continuing and you still have those lesson it is better to use the first one .let me know if you need me to explain more...

Yes