Hald and hard disk activity

[John]

With a fresh install of Kubuntu 6.06 all appears to be fine except the hard 
disk light briefly flickers every couple of seconds, even when I have left it 
with nothing to do for a long while.

Running "top" did not show anything major running, but the hard disk activity 
is very brief, just often.

Looking at "ps -aux" I started to kill processes. Eventually, I find that the 
excessive hard drive activity can be switched off by killing the six 
processes:-

hald-addon-acpi
hald-addon-keyboard
hald-addon-storage
hald-addon-storage
hald-addon-storage
hald-addon-storage

I am assuming that the hardware abstraction layer daemon is concerned with 
testing to see if any new devices are added such as USB items.

What problems will I find if I kill these processes?
Is there anyway around these?
Does the hard disk activity matter (Will it cause the HD to wear out faster?) 
or should I leave it alone and put up with the constant flickering of the 
led?

John