A Wifi Booster Question [View all]

I heard that I could use my old router (Cisco WR120N) to become a booster for the rest of my home since the Comcast WIFI sucks for distance. I was going to just buy a booster, but then a techie friend told me I could just use my old wifi router to be one. How would I set something like that up? Does it have to remain attached to my laptop after programming it? I do have a relatively central place for it in our hallway and it would sure be nice if it would send that signal a little further. Thanks so much for any and all help about this!

Cat in Seattle