Thank you for your replies. The idea of spreading the books out was a good one, except that we own more books than anything else. We'd end up distributing the other stuff among the books instead.
We're going with small boxes, quite a few of them in fact. About a hundred I think.
At one point, we hoped we would get rid of a significant number of books, but we're always weeding our collection anyway, even if our home doesn't look like it. So we're packing them all and it's been kind of fun--handling every one of them, being reminded of what we have, discussing them, reminiscing about some of our great finds at flea markets, etc. Heard most often: "I really should read that again."