I have successfully set-up a d-link wireless network but it is unsecured. How can I make it secured so my PC will not be at risk? I am not really into PC. Thank you.

You can secure it with using network key or just follow the steps show in the link
How to Set up a D-Link Wireless Router | eHow.com

I would like to suggest calling customer service of the manufactur that your router is. [I.e. Linksys]

I went through a whole bunch of online websites and well I'm not the very bright when it comes to technology.

It was pretty simple and easy when technical support took over for me.

Well this is just my two cents :)

Sarah