I "Archive" all my mp3's onto DVD+R discs as well as onto backup drives.
My concern is not so much the data or the music as it is my time in having
created the mp3's in the first place and the time spend creating/editing the id3 tags.
And not only are they playable on your computer, but there are car stereos
on the market that will play mp3-DVD discs.
As will most home DVD players