iTunes easily makes playlists. You can burn them to cd if you feel so inclined, or use a disc burning program to effect the same function.
The sound quality of the digital recordings is so far superior to magnetic tape, that, other than pure nostalgia, I don't see a reason for holding onto cassettes. I still have a handful of them, but really, I should replace them. The public library used to take donations of them, but now I just put them on Craigslist for free, and I never have trouble finding people who want them. It's amazing how many people there are who have amassed huge cassette collections from these giveaways.