I've just had a similar problem having changed a read only CD/DVD drive to a CD-RW one. Whilst the BIOS and system manager could see the drive it disn't show up on "my computer".
However, when exploring drive management and looking at the drive letters I noticed that the CDD was now F: whereas the previous one was U: (due to drive conflict problems).
When I changed the drive to U: everything became operational and I'm now burning away.
I hope this helps.