CDs are the best. Make my own digital copy, keep the original as a back-up.
16-bit/44.1kHz is perfectly cromulent for human hearing.
Greater bit depths or higher sampling rates don't result in any human-perceptible improvement. For production work it can be nice to have something more "high-res" to reduce the chance of introducing noise and artefacts during mixing, but outputting competently to a CD quality final product preserves all the audio information a human sensory apparatus can ingest.