> What does this mean, and do i have to worry about my harddisk:

 Yes, you have. At least I experienced severe problems after the
first messages like this occured - and lost all my data (I had
a backup).

> This is on a IDE-equipped i386 V1.2 system.

 This was my setup as well. Seems that NetBSD is not really able to drive
slow systems with IDE and programmed I/O. What kind of hardware (drive
and IDE-chipset) do you have?

-- 
Markus Illenseer