Hi Terry,
What do you want to end up with? A dual boot or an upgrade?
Yes, you can install Vista and create a dual boot with a full version disk
(you cannot do this with the upgrade disk). To do so requires that you
install it to a volume other than the one XP is installed on (to install
them both to the same volume will render XP unbootable). If you are
currently running a single drive/volume system, then yes you will have to
create at least one additional volume or partition to install to.
--
Best of Luck,
Rick Rogers, aka "Nutcase" - Microsoft MVP
Windows help -
www.rickrogers.org