C: drive needs d: installed to boot up

My previous computer has a 10 GB primary HDD (Drive C:) and a 2GB secondary HDD (Drive D:).

I sold the computer but kept the 2GB HDD as a secondary drive in my new XP system that comes with a brand new 30GB HDD.

The new 30GB is installed on the primary IDE and set as master. The old 2GB is also on the primary IDE but set as slave.

The strange thing is that the new 30GB HDD is partitoned as C: and E:; and the old 2GB HDD is D:

When I disconnected the old 2GB HDD, the computer boots up with a non-system disk error.

I do not need the 2GB anymore. How can I removed it from the computer without the computer hanging on the error message?

Richard