I just reformated my hard drive and now i can not get my ms-dos to come up. do i need dos to start formatting back to 2000??????

If you simply boot to the Win2K installation CD and choose new installation (with no repairs) - you will eventually come to a screen where you choose where to install it. Read the screens carefully at this point and create and format the relevant partition as you desire.

The only reason to create a partition in advance is if you want it formatted as FAT and for that partition to be greater than 32GB (the max FAT size for the Win2K formatter)..