I picked up an old IBM ThinkPad T20 to use as a beater laptop and tried to install Fedora Core 4.
The first problem I encountered was any CD I tried to boot from, whether FC4 or Knoppix 3.8, would produce endless I/O errors. Knoppix 3.4 booted fine. (Had I been paying attention I would have realized the CD was fine and the problem was elsewhere.)
After getting through endless read errors FC4 managed to struggle through an install and boot up. As soon as the first-boot configuration screen tried to come up, the machine locked cold. Every time.
It turns out that kernel version 2.6.11 has some serious problems with the T20. Executive summary --> it simply doesn't work.
See this link:https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=160958
Upgrading to 2.6.12 may help.