1.) Yes, Windows XP can do this natively.
2.) Yes, your XP Home upgrade can handle this.
3.) No, you don't have to buy anything.
4.) For the instructions, click here.
5.) Note that this is a one-way conversion...you cannot go from NTFS to FAT32.
6.) Note that you should NOT interrupt this process once it begins.
7.) Note that there may be a select few legacy programs that do not run properly on NTFS, but it shouldn't be a major issue.

Hope this helps,

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