Hi, BMHP.
The only real difference is that the Upgrade version searches your computer
for the presence of an earlier Windows version that qualifies for the
upgrade pricing. Unfortunately, Win95 does not qualify. If you have a
Win9x/ME or WinNT4 or Win2K CD-ROM to "show" WinXP Setup when it asks, you
need not have the earlier Windows actually installed on your machine. If
not, you'll need the full version of WinXP, either the Professional Edition
or the Home Edition.
RC