I've struggled with this myself. I'll tell you what I've discovered so far.
When it only presents you with the "Manually Install Driver," that means it hasn't found the actual driver. Even if you select the correct driver from the manual list, that's no guarantee that the driver actually exists on the system, and in my case the driver did NOT exist.
I had to download the driver and install it.
http://madwifi.org
I'm able to configure the wireless card after installing the driver, but I can't ping anywhere ... but that's another story.