You will be assimilated.
Ok, seriously though, that warning will appear anytime a change is made that
affects the system file set or anytime a program is installed or attempts to
modify code on the OS. Generally, once a system is set up, you will not see
that warning very often but it can be very annoying initially. The design is
for security, it keeps unwanted malware from installing itself without the
user's knowledge. While you can disable it, as mentioned by others, I would
recommend against it specifically because you will be then leaving yourself
vulnerable to the exact problems which it is intended to prevent. Also, some
Vista-compatible applications and routines expect it to be there and
running, and will not function properly if it is disabled.
Instead, I might recommend that you disable it temporarily while customizing
the system and installing software, then re-start it for normal use by you
and your family (you never know what the kids will attempt to install,
wittingly or unwittingly).
--
Best of Luck,
Rick Rogers, aka "Nutcase" - Microsoft MVP
Windows help -
www.rickrogers.org
My thoughts
http://rick-mvp.blogspot.com