|Why do you want to use DOS? You can delete/create/format partitions using the XP disk.|
Do you have a floppy drive? Boot off a WinME boot floppy, run FDISK from the A:> prompt, delete all partitions, then recreate new partitions. However, you will have to format using FAT32.
Another option would be to use the software available from the HDD manufacturer, or use a 3rd party partitioning/formatting tool. UBCD should have what you need: