I'm an OAP with a Linksys router.
Your router should have security settings to stop other people wirelessly connecting without your permission. You want to block them (as your laptop is now). To do this, you can choose either WEP or WPA in your admin settings. WPA is by far the better of the two.
Now, if all your pcs and laptops are connected by cable during this setting up phase, when you unplug them, they will automatically connect wirelessly - they will 'remember' the WPA key (password to you and me).
I suggest then when you open your admin pages you spend some time looking through them and getting to understand them. Don't forget - if you lock yourself out accidentally, you can always connect back up and reset.
It is something to get to grips with, not be frightened of.