"burn", not "copy"
A CD player will play an Audio CD (Compact Disc Digital Audio), not mp3 files. So by simply copying the mp3 files on a CD will not produce a playable CD for your CD player.
If a player is labeled as being able to play mp3 files, then a CD with mp3 data files can be played. The difference is huge, Audio CD can only hold 80 min of music. But a data CD has 700MB, and a decent quality mp3 can be just 7MB, so a CD can hold 100 songs or more!
But, most softwares, including the free Windows Media Player that is in every PC, can burn an Audio CD from the mp3 files. Basically the software takes the mp3 files, convert them and make a Audio CD that can be played in regular CD players. All you need is a CD-RW drive in your computer and a blank CD-R disc.
For detailed instuction and screenshots using Windows Media Player, please visit this link:
Also, although a CD-RW disc can be written again and again, truly old CD players might not read Audio CD created with a CD-RW disc. So stick with blank CD-R discs.
You probably don't have any recourse except to burn a regular music CD
You can always burn a music CD with windows media player and that CD will work in most older CD players.
|Sources: My answer|