As for installing an older OS on a newer hardware -- you may still run into problems relating to hardware compatibility. Found this out when I was trying to reinstall XP after I had replaced the motherboard (the original motherboard had failed). The XP install was the original release, and it appearently will have problems on dual-core machines (the install crashes saying something about PCI failure). I was able to get the install working after burning a new CD-ROM with SP2 slipstreamed in.