OK, so much for the easy solution.

Can you use the mount-device icon (described by sledgehammer) to mount a cd/dvd?
If so, the problem is most likely with Hal for some reason.
Unfortunately, I am not an expert in kde. XFCE, has a "Removable, Drives and Media" application in the settings menu, I don't know if KDE has anything like that.
I'm probably going to bow out, in favor someone a little more versed in your flavor of vector.
However, a simple thing to try would be to go to vasmCC -> Hardware --> Mounter and reselect HAL as your mounter of choice.