If I'm not mistaken, the creation of the partitioning was done during the low-level (i.e., hard) formatting system. That is done BEFORE the installation of the Operating system such as Windows. Hence, the partition will remain as is and if the partition definition (or parameters) is removed, the secondary disk identification may have been removed but it goes into the netherworld--since the contiguity of sectors and clusters cannot be established. Therefore, the primary drive (C will remain functional but the previous partition drive (D will not be usable.

The only solution I can recommend is to reformat (at low-level) the original 160GB HDD which will effectively remove the partition and identify the whole disk as a single drive medium. Then you reinstall Windows as your OS (Alas! All other programs you may have installed will have to be reinstalled, too.). I presume that the reason you want the partition removed without compromising the original contents of Drive C: will be a) you don't have the Windows Installer CD and/or b) you installed other programs that you are not sure you can reinstall after installing a fresh operating system.

Just a minor comment, really.

-Goitz