Can't boot: "hda: lost interrupt" after possibly screwing up kernel.

[Adam <a24061@yahoo.com>]

I am (was) running Debian testing on an Athlon 1100.  Since I last
successfully booted, I added the hotplug package and the line usb-storage
to /etc/modules.  I was trying to get sensors to work, which downgraded my
kernel (from 2.4.23) to 2.4.20.  I then removed kernel-image-2.4.20 and
added kernel-image 2.4.23-i686.

Now my machine won't finish booting.  It appears to load the kernel,
recognizes all the drives, then goes into this:

hda: attached ide-disk driver.
hda: lost interrupt
hda: lost interrupt
....
hda: dma_timer_recovery: dma status = 0x64
hda: DMA interrupt recovery
hda: lost interrupt
EXT3-fs: mounted filesystem with ordered data mode
hda: dma_timer_recovery: dma status = 0x64
hda: DMA interrupt recovery
hda: lost interrupt
hda: dma_timer_recovery: dma status = 0x64
hda: DMA interrupt recovery
hda: lost interrupt
....

/boot still contains the 2.4.23-i386 files.  Or is it a module problem?

I am extremely desperate to get this fixed as I need to get some work done
tomorrow!  Where can I get a good Debian rescue disk?  (The links on
http://www.debian.org/releases/potato/i386/ch-boot-floppy-techinfo.en.html
are invalid.)  Is that the correct approach?

Help would be very gratefully appreciated!
-- Adam