How Can i use my laptop in my home using a wireless router. And Not have it constantly be plugged in?

I do not have a regular computer with a tower and monitor and all that good stuff. All I have is my laptop. I have a linksys cable modem, and a cisco wireless router. I have already installed it and i plugged everything in the way it said to. BUT i have to have to wireless router plugged into my computer. I want to be able to take it to my bedroom and all throughout the house. I have once before had it like that, but something happened to our internet connection and it reset itself. Please help!