Download Antix Linux 8.5-486 if you have a very old computer, such as Pentium I. Download Antix Linux 8.5-686 if you have a Pentium II or later. The 486 version will work in just about any computer.
Downloading Linux and burning it yourself to a CD may be too much of a hassle for some people. An easier way is to buy a cheap disk from an online vendor. OSDisc.com sells Linux disks for $1.95 apiece, including the latest versions of Antix and Crunchbang. (Click "Live CD" and look under "MEPIS" for AntiX.)
If the wireless adapter doesn't work, you can try another version of Linux, including an older version of the same software. (For some reason, only older versions of Antix Linux work with my D-Link wireless card.) If you saved your receipt, as I advised you a few paragraphs ago, you can exchange the wireless adapter for another one.