if someone in your family knows how to access thr router information then you can set the ssid broadcast to no so the network name wont show on a scan for networks. thats usually the best way to do it if you want maximum security.

make sure once you connect to your own network you go into the network settings , and it depends on your os your running to set it to connect auto maticaly if in rand of your network then once it does turn off the ssid broadcast and or just enter the network information manually.

keep a strong key for your network as well. dont use common words or names. use upper and lower case numbers and letters in unfamiliar combinations.

hope that helps. as for the battery. its a crap shoot each time we get one for our laptops. i personnaly keep my laptops plugged in and running constantly and when i go out they are always charged. its good to let them drain all the way every few charges to keep the charge strong.

roger.