Chief among the books I've read that I truly didn't enjoy until the second time was The Lord of Rings, but I don't know if it had as much to do with where I was in my life the first time I read it, or if it was just the aftertaste of that cheezy animated version I was subjected to as a kid. All I know is that after watching The Fellowship in theaters, I re-read the whole trilogy a second time, and found a lot more depth and excitement in it than I did the first time.
It was the same way with WoT. The first time I tried to read The Eye of the World, I just couldn't get past the first chapter. I tried again a few years later, and once I got past the first chapter, I was hooked, and spent an entire year reading the rest of the series, all the way up to Winter's Heart (which was the most current volume at the time).
Who knows? Maybe someday I should go back to other books I "just couldn't get into" at the time, or ones I never finished reading, like Desperation or Dune.