You can use any DVD/CD burning software like Nero, Alcohol 120%, DVD Decrypter...you just create an image file!
Using nero, create the CD or DVD as you usually do but the last step, before you say "burn", click on the source and change it from the CD or DVD writer to "Image File"
Then, click Next and specify the location.
You can choose between .nrg or .iso
BTW, If you are creating the .iso to mount it on a virtual drive, then even .nrg (Nero image) works.
If you need to mount it, use alcohol 120%...it has virtualk drives or you can use daemon tools