vista is slower than XP... and if u copy a file it isnt the OS(oprating system) that depends... it is just the disk.(how fast the disk and CPU is)
Vista take aloot of memory. so to say it... i would just use vista to media. not games or hard stuff like HD movies and RAW HD editing.
Vista have something called directX 10.(it will get beather grafic) it is esensial to play newer games(they run on 9 tooo). XP ordinarily just come with directX 9.0c(most used today but 10 is comming fast) but u can uppgrade it to 10. hope u understand so far XP
and the new Widows that is still in Beta.. is preatty good. it is Widows 7. it dosn`t use as much ram as Vista. and it is more usable to games. tough u can only download the beta until 20 aug.
and if u still want to use vista i recomend u to get more ram. u need atlast 4gs to run it smoth.
so if u are in to games and stuff like that... u sugest u get XP or Widows 7.(i can link it) but if u still want to use Vista i recomedn du to get more ram. but if u get 4gs... the PC still cant use it all

(gets complicadet agen)
bc a 32bit vista or wathver OS u use. u cant use more that 3.5gs or somthing like that. if u want more RAM(up to 32gs) u gotta get 62bit. but then u cant use all the 32bit software u have
But in the end... get more ram... that is the most important factor of the PC after the CPU and grafick card
PS: Vista dont have beather grafic.. that is the gamemaker who deside

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here is the link for widows 7 (it is wery good i have used it for a half year now

) DOWNLOAD THE 32Bit version!