This is a gem. This software can’t be found via a regular search on Microsoft Downloads. This is a free program (Unsupported by Microsoft PSS) for Windows XP, 2000 and 2003 that lets you create a virtual CD drive on your hard disk. Supported file formats are: .udf; .cdfs; .jo; .iso; .rock. It weighs only 60KB in size.

Installation instructions (copied from the included Readme)
============================================
1. Copy VCdRom.sys to your %systemroot%\system32\drivers folder.
2. Execute VCdControlTool.exe
3. Click “Driver control”
4. If the “Install Driver” button is available, click it. Navigate to the %systemroot%\system32\drivers folder, select VCdRom.sys, and click Open.
5. Click “Start”
6. Click OK
7. Click “Add Drive” to add a drive to the drive list. Ensure that the drive added is not a local drive. If it is, continue to click “Add Drive” until an unused drive letter is available.
8. Select an unused drive letter from the drive list and click “Mount”.
9. Navigate to the image file, select it, and click “OK”. UNC naming conventions should not be used, however mapped network drives should be OK.

Direct Download link