Got this in my email, it was supposed to be a reply to your post, so here goes:
Easy solution. From the Start:Administrative Tools, open the local Computer Management Console. Then, if it is not already open, open the Storage object by clicking on the plus sign, otherwise, click directly on the Disk Management object.
On either of the right panes, right-click on your CD-ROM drive and select the \"Change drive letter and Path.\" When the dialogue box opens, click on the edit button. On the \"Assign a drive letter,\" click on the down arrow to open the drop down box. Using the scroll arrows, select the drive letter that you desire, and click OK. After that, close all dialoged boxes and you are done.
FYI: If this computer is being used on a network where you will occasionally be connecting to network shares, consider using a drive letter for your CD-ROM that always keeps it above your mapped drives. It can sometimes get confusing trying to locate your CD in amongst all of the other network junk.