I've got a D-link DWL-G520 with Atheros chipset. Works fine under Mandriva 2008.1 for x86_64 (driver built in to kernel 2.6.24.4, ndiswrapper probably would have worked fine instead).
I've used ndiswrapper on past machines, it is a good solution. Often there is a special text file list that can FORCE modules like ndiswrapper to be loaded, this often improves hardware detection. And sometimes it takes manual editing of configuration files to get the settings (ESSID, channel, etc.) to stick.
Dedicated forums can help you with these two tasks:
Ubuntu forums:
www.ubuntuforums.org
http://www.ubuntu.com/support/community/webforums
Mandriva forums:
http://forum.mandriva.com
I don't want to sound evil ("read the manual"), but if you update your distro, you'll be reading stuff and looking at forums anyway (to set up your video driver, printer, camera memory card reader, etc). And things do change between distros, and even from one release to the next (and hardware support improves!).
EDIT: Right now, I am having problems getting my configuration to stick so that WPA security will work, so I know how you feel!
Please, PLEASE let us know how it goes. Don't underestimate the power of hackers helping each other out!