Currently this saddle valve is exposed but I would like to close this wall up. Before I do I'd like to know if I should leave the valve as-is or if I should remove it. If I remove it what is the best way to do so?
This used to be a valve that fed a refrigerator. We turned this off some time ago.
Update
I wanted to give everyone an update and hopefully help others looking for assistance. Based on the responses I received I went with a Sharkbite 1/2" coupling (not a slip coupling), and it was pretty straight forward to install. Thanks to all for your feedback.
Best Answer
Ed has the important part of the answer. Saddle valves are trouble, and since you're not using it, it's easy to eliminate. Even if you were using it, it makes sense to replace with a soldered-in valve.
If this is copper tubing, it might be pretty easy to replace this valve with a slip coupling. It is especially easy if the tubing is long enough to flex it laterally to slide a coupling on. That is a straight copper coupling that doesn't have a ridge or other bumps in the middle.