Hi Enzo
Of course not, PixInsight runs without flaws on all versions of Windows XP with at least SP2 installed.
Which archive did you install? Did you install a 64-bit version of PixInsight on a 32-bit Windows? If you did so, it won't work.
If your Windows is 32-bit, you must install this file:
PI-win-x86-01.02.00.405-nsi-20080716-c.exe
Regarding Windows Vista, I must say that since SP1 most problems have been fixed, and now it runs reasonably well (considering that it is Windows, after all :lol:)
Anyway I don't like Vista at all, so I can feel with you. It's shinny and the Aero desktop looks really fine, but its use of the available resources is far from optimal, especially for serious/professional work. I just use it to compile PixInsight for Windows