Another thing to consider: The Vista Upgrade only installs from Windows, so
anytime you need a complete reinstall of Vista, you must first reinstall XP.
No more 'sticking the XP disc in for verification' before install as before.
So, keep your XP media. If OEM, get a copy of XP from your system
manufacturer if you don't have 'restore' disks with OEM XP on it.

Otherwise, you will be stuck. Your hard drive copy of XP will be gone, with
no way to restore it and Vista won't install by itself.

IMO, your best option is to buy the retail version. It can be installed on
an empty disk.
"titus12" <titus12@msn.com> wrote in message
news:ugfH5wlPHHA.4376@TK2MSFTNGP02.phx.gbl...
> Will it be better to install Vista over WinXP Home or do a clean Install?
> Will Zone Labs have an update ready when Vista goes on sale?
>
> Thank you;
> David
>