Use a 3rd party boot manager program that allows you to hide the operating
system you are NOT booted into.

Hi Peter,

Very true, but there are a few ways of avoiding it. One is to use a boot
manager that allows you to select which volumes are available to each
installation and not load the Vista system volume when XP is booted. A
second is for users of Bitlocker which (available to only certain versions
of Vista) will block XP from altering anything on the Vista system volume.
More on this from MVP Bert Kinney here:
http://bertk.mvps.org/html/dualboot.html

I wish I had a nickle for everytime this really moot academic problem that
MSFT created because their system restore team was simply  too lazy to write
the code to fix it comes up.

It's simply not a problem if you exercise simple file path management.

For cryin' out loud people--what earthly reason does anyone have to go to
the XP boot on a dual boot?

You have a dual boot. You're on the Vista desktop.  You wanna copy or access
files on your XP boot. Do ya boot to XP?  Hell no. Whadaya do?  You simply
type in the IE address bar the following:

XP Drive\Documents and Settings\*Your XP Profile\Desktop

Then go to the address bar of the folder that pops up and drag the little
inconnete to your desktop and you have a shortcut to your XP desktop and
access to your files and folders on XP.  End of problem.

As Jimmy Gandolfini would say "Baddafringinbing--ya done."

Simple as fringin' that--the pomp and circumstance over MSFT's pure and
simple laziness to prevent the problem that they didn't protect the restore
points is hugely over hyped.

Yeah-- you can use a 3rd party boot manager--yeah if you have the right
Vista edition you can protect the restore points with Bit Locker encryption
but you simply  don't need to if you take the 3 seconds to make the short
cut I just showed you.

Good luck,

CH