Cd-rom drive not attaching in Windows 2003 Virtual Server

Hi folks,
Please accept my apology if this is the incorrrect place to enter this
question. I have Windows Virtual Server running on Windows Vista. No matter
which channel I select, I cannot get my Windows 2003 vhd installs to see my
cd-rom drive on my Dell Optiplex GX620. The drive works fine in Vista. Is
there a registry setting or some hidden location that I can access so that
this cd-rom drive is accessible?
The reason this is important to me is I'm trying to install IIS on my
Windows 2003 vhd installs, and the install cannot find iisback.vbs. The file
is named iisback.vb_ on the cd, so even if I point it to a folder where I
copy the cd, it doesn't work, because it apparently needs to extract the file.
I've also tried pointing to an iso image, without success.
If we can't get the cd-rom drive to work, could you give me the files I'll
need to extract to successfully install IIS and a method to extract them?
So, I'm feeling pretty stuck, and I appreciate your help!