Mike.... yeah if you want to register the song and use the 2 CD's... the only thing that matters is that the CD plays on an audio CD player.
I have not registered a song with the US Library of Congress in many years. I do believe you can now submit the songs electronically as wave or MP3 and do all the filing and paying on line. Have a look at copyrighting the songs as a collection as opposed to individual songs..... you save a ton of money doing it that way. That was how I used to do it.....wait until I had 3 or 4 songs minimum and register them as a collection for the same cost as one song.
Last time I copyrighted a song, I sent in a cassette tape.... that's how long it's been.
I do not copyright my songs with the LOC. Here's why. I have Masterwriter songwriter's software. It comes with a service called SONGUARD where I can register the song with their secure servers and I get a time/date stamp on the music/lyrics and get a print out. It's fast and included with the software.
Note: there are other 3rd party stand alone registration companies if you wanted to go that route. Google search for them.
In addition.... if you place any song on any music website like Soundclick or Reverbnation, etc... the servers there also time and date stamp the file when it gets uploaded. A copyright is nothing but a time and date stamp verified by the Library of Congress. Should legal redress be needed on a song of mine, I would need to file a LOC copyright to take it to a court. I have proof that I registered the song previous to any other copyright, and the lawyers will sort that out. Just having a LOC copyright means nothing when it comes to a jury and a judge. It depends on how convincing the lawyers for each side are with the jury.
Truth be told, the majority of songs are not in any danger of being stolen. Most reputable publishers and music industry reps will not even listen to your songs unless they ask YOU for them. It's to protect themselves from lawsuits. As a song writer, I have been trying to get people to listen to and use my music for decades, and as hard as it is to get them to listen..... no, I don't think anyone is trying to steal my music. Even the writers with a string of #1 hits still have to get in line and jump through the hoops to get their new tunes on the desk of the producers and managers.
I know a guy with six number one country hits with big name artists. If you listen to country music, you have heard his songs. He moved out of Nashville and back to this area and plays on weekends as an acoustic act in small clubs for fun and drives a truck Monday through Friday.
If you want to copyright the music so you can sleep better at night, by all means, do so.
One final thought: If a legitimate music publisher does hear your song and wants to sign it.... they will be obtaining the copyright in their company name. If you have registered it in your name previously, it causes more paper work for them. I was advised by a very reputable publisher not to copyright and not to register my songs with the PRO I am with since when he signed my songs he would have his company handle all that and there would be no double registrations in the system that would cause confusion later in regards to payments. This advice is echoed by other writers I know who regularly place works with libraries and publishers. Dealing with legitimate companies, this is not a problem.