Your receiver is only telling you what signal is being detected from your dvd player. You could only have two front speakers connected, and it would still show 3/2.1 if that was the signal being sent. 3/2.1 means it's detecting a 5 channel signal. If you change your source to two channel stereo, it will read 2/0 regardless of the number of speakers connected.
BTW, your receiver would show 2/2.1 if it displayed in a way that you were thinking.
The 2 meaning 2 fronts.... The other 2 being 2 surrounds plus the .lfe.
Donny, 5 channel surround= 3/2/.1 on your receiver display.
The three represents that your receiver is detecting three channels of audio for the front, and the 2 represents it's receiving two surround channels, and the 1 represents that it's receiving the LFE channel.