The best way IMO is to format your HDD and do a clean install of XP Pro. Windows is more finicky with other OS's so the clean install will ensure that you won't have any "issues."
If at a later time you want to try a XP Pro/Ubuntu dual boot, then you may want to format and partition your HDD into two partitions, using NTFS. For now, you can use the second partition as your Files drive (the first for the OS). Then later you can reformat the second partition as Ext4 (default file system for Ubuntu) and install the Ubuntu OS on the second partition.
#1: Obsidian Black Mini 9 | 2 GB Kingston HyperX CL3 | 32 GB Runcore IV | 32 GB Transcend | 1.3 MP Webcam | BT | Sound & Mic Fix | OS X 10.6.7 | NBI 351 | A07
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