you can overwrite it with your XP CD though, NTFS is only writeable by microsoft I believe coz they own it. Do it in FAT32 especially if you ever want to partition linux or anything, coz only FAT32 is fully interchangeable for reading&writing to disc.
When you stick in yer CD choose install complete or something for a complete overwrite, or you could try the maxtor reformatting tool for just a formatting, cant find the address atm but its on the maxtor site.
What OS is installed atm?
[edit] not maxtor western digital, Western Digital's own free partitioning utility, "Data Lifeguard Tools V. 11.0":
http://support.wdc.com/download/index.asp?cxml=n&swid=1