First things first - your "secure" wi-fi connection is not on your laptop - it's on your wireless router. The router would have been set up to be secure, either by yourself or whoever set up the router for you. Anyone wanting to access the internet via your wireless router, will need to know the "key" (password). This has already been set up on your laptop, hence you don't need to keep inputting the key.
Your laptop scans for other wireless routers and it seems like it has found another router, located nearby and this is not secure, i.e. anyone can use it, as there is no need to input a key.
No need for alarm in my opinion, unless I'm misinterpretting what you're saying ............