As long as your surround receiver has pre-amp outputs, it is not that difficult at all.
1) Hook your DVD player up to your surround receiver.
2) Connect ALL speakers EXCEPT the mains to the surround receiver.
3) Connect the "main" pre-amp outs from the surround receiver to one of the inputs on the stereo receiver.
4) Connect the main speakers to the stereo receiver.
5) Connect a standard CD player to the stereo receiver.
Now, the mains will always be driven by the stereo receiver. Just choose the source you want - surround receiver for movies, or CD player for music.
This is especially attractive because you have taken some of the load off the surr rec when watching movies.
