Hello, my name is XXXXX XXXXX I will be glad to assist you with your problem.
First off, the difference between a secured and unsecured wireless network has to do with the security settings in the router, not the computer.
A secured connection require a password XXXXX connect. An unsecure connection means there is no password XXXXX anyone within range of the signal can connect.
If the linksys router is yours, then follow the below steps to make it secure. (It will be easier if you can do this through a hardwire connection)
For the default Linksys settings try this below
1. Open a web browser of your choice
2. In the address bar type in: http://192.168.1.1/
3. It will ask you for a user name and password. Leave the username blank and the password XXXXX XXXXX
4. Now click on the Wireless tab and you should see something like this
SSID is the name of your network. I would recommend changing it to a name of your choice.
5. Once changed, click on wireless security. I would recommend setting the router security mode to WPA Personal with TKIP like the image below
6. Now enter in a Personal key or password XXXXX your choice.
7. Now on your laptop, take a look at the wireless signals and find yours and click connect. Now it will ask you for a password. Enter in the password XXXXX you created and now you will be on a secured wireless network.
Please, let me know if you have any problems and I will be glad to further assist.