An upgrade copy of XP Pro will work for you. My preference would be to start fresh and not just perform the upgrade on top of XP Home. You will need to save your data. Also, inventory your programs and make sure you have copies of these and all your hardware driver disks. To use the Pro upgrade with a clean installation you will still need a qualifying MS disk at some point during the installation. An XP Home retail or OEM disk will work but a recovery disk from Dell, HP and such is not going to qualify. I might offer one suggestion that will allow you to save your XP Home installation until you are fully set up with Pro. When you buy the XP Pro, get another hard drive as well. Install the hard drive and let XP do the partitioning and formatting during the installation. Make sure your copy of XP has SP2. Once it's up and running, you can install your applications and go through the tedium of tweakin it to your liking. From here, you can temporarily reconnect your XP Home disk and copy all your data over to the new drive in a folder you create until you can distribute it as you wish. You can even leave the drive in for extra storage and format it later. Don't activate the OS until all this is done. Hope this helps.