ok, in that case...
1. hook up your computer to the router via ethernet
2. (you'll need the guide that came with the router for this, so find it before doing what I'm about to tell you) there's a little pinhole somewhere on the router. this is a manual reset. put a paper clip in there and hold it for about 10 seconds.
3. type in the IP address of the router into your computer's browser, and use the username and password supplied in the instruction manual to log in. from there, you should be able to set up the router to whatever specification you want. And if you set up encryption, just remember to have the same encryption key on both the router and the computer, and it will work fine.