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I have several old XP boxes that I would like to convert to Linx. I have a boot/install disk for both Ubuntu 8.04 and Xubuntu 8.04. I would link to make a boot/install disk on a CD (not a DVD or flash drive) for Ubuntu 12.04.2L. How do I do this? Please provide the specific steps I would need to follow because everything I have tried to date is not working. Alternatively, if this is not possible, could I install 8.04 and update to 12.04?