Hello, not a silly question at all sir. Very good question. The short answer is no it will not break it.
What you are seeing on the _s1 is the first stream name of the camera. In VSM 6.x there are 3 parts the IP Camera, the Stream and the Archive.
What i recommend is renaming all 3 to match your naming scheme and if you are running 2 streams from a single camera then at the end of the stream name make it _s1 and _s2.
As long as you are just changing the name it will not cause you a problem on the archives. When you start changing items like bit rates etc that is when it will stop your archive and start a new one.
thanks and hope this info helps.