I doubt deleting the songs will help.

You need to remove the DRMs off the albums before they are usable. It is wise to remove DRMs right off the bat. They can only be removed when the DRMs are working fine and you can play the music. The RIAA tried to out law all DRM removal however, if the company that you bought the tune from, goes belly up and they stop supporting their server your DRMs supported by that server, die. Millions of tunes have died that way.

The reality is, like we all will die, so will the DRMs. It is only a matter of time.

Then do not use itunes to sync. Check out the top sticky in the audio forum. Near the bottom of the sticky there is a link to a review of 50 sync apps quite a few are free.

I think I have warned you about DRMs before. If your computer dies that has the licenses (itunes) your DRMs die. Apple may or may not help you to recover your licenses. I assure you they will not be helpful. They prefer that you buy them all again.