I dont want to remove the DRM--just move them somewhere else before I converts non-DRM-ed songs since most converters (say going from WMA or AAC to MP3) will choke once they him the DRM-ed songs. An app to change the icon of DRM-ed songs would be great, but I would settle for a list too (as, in my case all songs will be in the same directory). Any ideas?

Straytoasters

For wma/wmv DRM files you can change the folder view to Details. Then add "Protected" detail column and simply sort by "Protected" to weed out those files. If you have many songs in many folders, you can use search to list all files and then sort by 'Protected' as well. Not sure if this will work w/ other file types however.

You might try looking in the preferences of whatever converter you use to see if allows automatic and/or silent continuation if it encounters an error.