Cheapest thing would be to buy a wireless N for the range and just use the wireless G adapter that's built into the laptop.
I just got this to use as a switch/accesspoint in addition to my old d-link: http://www.newegg.com/Product/Produc...82E16833124284
It gives a better signal to my Wii that's in my basement from my bedroom on the second floor, than the D-link (also wireless G) does from the main floor.
But if you just go wireless N for the router and leave everything else as is, Any Wireless N (I'm going to prefer Linksys again) would work. I have set up this: http://www.newegg.com/Product/Produc...82E16833124081
and it couldn't have been easier. Then again, all Linksys routers are a pretty easy install.