I need some help deciding what media for music

I have a requirement to provide a copy of my rather large, (600+), album collection to my ex-wife.

I have been trying to do this onto CD's but the final product has been less than reasonable. The biggest issue is significant pieces of the songs not being copied or being unplayable.

I was thinking the other day that maybe I could just buy an MP3 player and provide copies on that media. Or maybe USB sticks. Or external hard drives?

Any ideas what would provide the best solution at a reasonable cost?

Thanks

What is the size of the data? USB Flash or External HD would be ideal. CDs or DVDs would take too long.

When burning music to data dvds, slow the burn down to a max of 8X, 4X is even better, that way the burner has time to burn everything to the disk.
Learned the hard way too.

Data DVDs are a good backup, but as brought out, USB Flash drives are good for transfering files and External HDDs , if you use a couple , with one off site , can transfer and archive data.