Assuming there is a 'headphones' plug on your dictaphone (and a microphone input on your PC), you can connect the two together with a male -- male connector (probably 3.5mm standard jacks).
Then use a free program like Audacity, which will be able to record the audio from input (i.e., your dictaphone).
You can then save this as an mp3 file (or whatever you want), then copy to CD.