1. Unless you own a mansion with a huge library space (and two maids to dust it!), at some point, one has to set a limit as to how many books one will keep! And reasonably, the number of books should be limited to what sensibly fits in the space available to safely keep them. That means on shelves, not stacked all over furniture surfaces and the floor! I own 6, six foot tall bookcases (about 2 feet wide each), and decided some years ago to limit our book collection to what fits on those shelves.
2. But more than that, if one is going to allow room for new additions to the collection (inevitable in a book loving family), then one needs to regularly pare down the collection to LESS than comfortably fits in the space available, and have a rule that when new ones come and exceed the available space, some old ones have to go.
3. There are some really good books out there - and an incredible amount of junk! Be very selective!
4. Just because it's a "classic" doesn't mean you and your family will actually like it. And what good is a book you dislike so much you never finish reading it?? It's not that important. Let it go!
5. Reading tastes change over time, and with the ages of the kids. And that's healthy. Just because it used to be a family favourite, doesn't mean you need to keep it forever. Thinking you'll want to read them to your grandchildren one day? Set a limit and keep only a few really, truly enduring favourites. Say 12, or 20. No more!
6. If you've read it, and it's not one of those books you're really excited about reading again, let it go! Let's be real - only very special (to us) fiction usually gets re-read. Non fiction needs even more selectivity - something that is a very useful reference to a favourite topic is worthwhile, if you use it. Something you think "might come in handy one day" isn't.
7. No matter how much you want to think otherwise, I promise you, you are NEVER going to read ALL those books to your kids you think you will, nor are the kids going to be interested in ALL the great books you've collected for them. And even if you do and they are, you can NEVER collect enough books to keep ahead of the reading appetite of a 10-20 yo! So stop trying. Get them a library card. Or maybe 3 (to different libraries).
8. In the end, I think the 80/20 rule applies very well to books - 20% (that's 2 out of every 10) books you own will provide 80% of the total value and enjoyment. The rest will provide very little. Or none at all. Now if you can identify that 20% and cut out most of the rest, you'll have a lot less clutter!
Didn't take long for nearly everything to be snapped up.