In China, if you call anyone as 老不死, you are not praising him as "old and not died". In fact, you are asking him "why don't you go die?". So we think it's so impolite to call anyone 老不死, especially ...
I read a book while having dinner. You can see 吃 as an adverbial clause of time.
YI2 GE4 or yi2 ge5 are both correct, and it depends on where you using them. When we use 一 and a quantifier together, we always proniunce 一 as Yi2, and there is no specific reason.
Just 书 is enough. This is the most natural to answer such a question, and no need to say more.