Disabling "System Volume Information" on external USB drives

I have three computers. One is a Desktop with Windows98/2000 dual
booted. I have another desktop machine with XP-Pro (SP3) and a Laptop
computer with XP-Pro (SP3).

I have a large external hard drive that plugs into USB. I backup all 3
of these computers to that drive, by simply copying all my personal data
to folders (named "Laptop", "98-2000" and "XP-Desktop"). I prefer
backing up this way because I have an exact copy of my data which can be
accessed by any operating system. This external drive is huge, so I can
fit all my data, from all these computers, and still have lots of room
to spare.

My problem is that when I backup Win98/2000, I have no problem, but when
I backup either XP machine, it creates these folders called "System
Volume Information" on this external drive. I know that thing is for
doing a restore, in the event an XP computer has a problem, which is
fine for the actual computer. But I do not want this on my external
drive. Not only that, but since I backup two separate XP computers, I
tend to wonder if there is some sort of conflict between that folder,
depending on which XP computer I am plugged into.

Therefore, I am constantly having to delete "System Volume Information".
And delete it again, and again and again. Quite annoying!

Is there any way to stop XP from creating that "System Volume
Information" folder on external drives, once and for all?
Yes, I know i'll have to do this on both XP machines.