My problem with moving is always that once I've unpacked the books and the music stuff, I tend to lose interest so I end up with boxes of stuff lurking for months afterwards. Being married helps a bit, but my wife has her own blind spots and we still have boxes in the basement eleven years later that have yet to be unpacked.
If you threw them all out unopened, how many more years would it take before anyone noticed?
When it comes to moving books I measure in how many days it will take to stop being sore.