I want to delete C: Drive, where OS loaded with keeping other drive.
dude, if my understanding is right, you want to clean format your HDD (or one of your drives like C:\) without booting into that HDD.
So all you have to do is, connect this HDD as a secondary and boot windows (any version including win95/98) from another HDD (called primary boot device), right click on the drive from your secondary HDD (ie the HDD you want to format) and select format.
If you want to delete the partitions, you will have to use tools like partition magic or even win 7/8 embedded tool to shrink/expand (win 7/8 terms) the partitions.
PS:: I trust that you understand what I mean by partition, format, primary/secondary boot device and delete. In case you do not understand them, I advice you to check with our best friend (google) for more details.