If you want the simplest solution for desktop WiFi, buy an Edimax PCI card from Newegg for $19.99. Linux has built-in driver support for that card’s chipset. It is literal plug and play, no drivers to install. I have installed several of them. The card is also Windows XP compatible on dual-boot machines. If I can do it, even a caveman could.
http://www.newegg.com/Product/Product.aspx?Item=N82E16833315041
MAN,...that has almost 1500 reviews....they must have sold a bunch of those.
....no download needed...