IF your Dell has a Windows Vista CoA on it (if it was originally shipped with Vista)
ANY Dell "Vista Reinstall" disc will work. this is a matter of licensing between Dell and M$.
Try to get SP2 media as it'll save you some aggravation.
rare (but available) is Vista Ultimate Dell media.
But it works. you can pick up loose Dell reinstall media on ebay cheap.
As a commercially prod cued pressed media you have no worries about what crap some joker may have inserted into it.
That being said I'd really recommend using
Windows7 instead, but towards that end, some older Dell Vista computers
are "Twitchy" about Drivers when installing windows 7, so what I do
(And why I bought the Dell Vista re-installation media) is to install a clean copy
of Vista of the desired edition, install all the factory Dell drivers, let windows updates do all the updates it can find and after making sure everything works,(for a week) only then running Windows7 on as an "upgrade", that way the Win7 installation accepts the drivers....
Saves much aggravation.
An important note is that Vista Home can only be upgraded to 7 Home or 7 Ultimate
Windows Vista Business can only be upgraded to 7Pro or 7 Ultimate.
And you cannot upgrade from a 32bit os to a 64 or Vice-Versa, so be sure to get the Vista version that is most analogous to the windows 7 version you intend to run.
AD