While I wait to post my Hardy Heron upgrade experience, I thought I would point out a great tutorial on How-To Forge, for installing and configuring Kubuntu 8.04 as a near-perfect Windows desktop replacement.
While I disagree on some choices the tutorial author makes regarding application choices (there is no need for Adobe Reader in Kubuntu, with both KPDF and - my preference - Document Viewer; I prefer DigiKam to F-Spot for digital photo album management; I use Pidgin rather than Kopete for IM; I don't use Opera web browser; I prefer Kontact (KDE-PIM) to either Evolution or Thunderbird/Lightning; I use KAudioCreator for ripping my CDs to MP3; etc.), the author lays out a very good process for configuring a Kubuntu desktop with pretty much everything a typical (Windows) computer user needs.
(H/T: DesktopLinux)
The last page of the tutorial links to other similar tutorials, including a Perfect Ubuntu Desktop, etc. However, I think that KDE lends itself better to converting Windows users to Linux. YMMV
I may try something similar, and if I can get my (Windows XP, but soon to be Vista, using) wife to test-drive it, I'll report back on the experience.
What other applications or other configuration changes would you make to a Kubuntu (or any other distro, for that matter) to make it more comfortable and usable for Windows users?
And this discussion gives me a thought: perhaps we will one day see a Windows-transition distro based on Ubuntu - maybe something like "Winbuntu"? 
Hi,this is whisky,i was reading your post on a better OS then WINXP, i personaly
would prefer anything other then winxp,i just recently started to use firefox and i am
quite pleased by how it work,s compared to winxp.
My question is do we have any use for winxp and/or MS at all.
When are going to change to another os it,s a little scary to say the least you know
it,s like giving up your security blanket.
What,s the relationship between firefox& kubuntu are they one in the same or doe,s
one complement the other.
Right now i have a problem with winxp os need to download everything to external hd
then reistall winxp then put what i want backon pc hd,thank,whisky