Heh, Bookworm_Girl, you probably do know what I'm reading!
Thanks so much for the help and suggestions both of you!
I tried what both of you said regarding memory: reformatting, factory default, trying a new book, putting it back on main memory. None of that worked.
However, converting the epub to rtf then back to epub worked! It did mess up the formatting which sucks for poetry, but it wasn't that bad. But now it's lightning fast compared to before. Whew, disaster narrowly averted.
I suppose in this case it was the formatting or something; there were a lot of links for every poem, so maybe that's it? Or maybe the chapters thing I mentioned above?
Either way, it's great to fix it for now but I think the straw still did break the camel's back. I may be looking at buying a different reader soon. It's just ridiculous I have to jump through so many hoops and deal with such frustration to read and annotate my books!