Before you go any further, that is a major step. Is there a particular reason you want to go down that road? Whatever operating system you have you will need a boot floppy disk which you can get from here if you don't already have one click here You will then need to fdisk and delete all partitions and then repartition the disk how you want it to be and then format the disk(s). Then you would have to re-install everything from the original CDs.
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