Disk diagnostics

My computer runs RedHat 7.1 dual-booted with Windows 98.
I am having a problem under both systems where one of
the disks seems to be balking -- taking sometimes a
few seconds to respond. This is one of three physical
IDE drives, so the problem is sporadic.

If I hit the disk really hard, there is no delay.
I did a find -type f -exec wc {} \; across the
whole system and it screamed right through it.
The problem could be tied in with the power management
system.

Since this occurs under Linux, maybe someone can suggest
a raw-disk accessing technique that could help me to
isolate which drive is doing this, if in fact that is
my problem. Linux mounts all the Windows volumes
as well, but I think in this case it's the raw volumes
I want to play with, right?

Oh, and how can I build or download a floppy-only system
that will allow me to run apart from the hard disks?
(I'm looking for a cookbook, if one exists.)

Suggestions?

Thanks,

Vic