Nice questions! The worst book I ever read would indeed be Breaking Dawn, though that was to some extent still enjoyable (I'm more likely to see past flaws when the story is still enjoyable, even if it is unrealistic and ultimately bad). So I think my worst would be The Sword Of Shannara by Terry Brooks. Bo-ring!

Best book ever is hard to say... I was really impressed with The Emperor's Soul by Brandon Sanderson, even though the book was only about 175 pages... but the magic was so damn good and intriguing! I really liked how it was described. There are some other candidates for best book (The Way Of Shadows by Brent Weeks, or Myrren's Gift by Fiona McIntosh, really mostly because their magic is loveable. And the writers aren't afraid to put their characters through hell) that I can think of right now, but I've read them a long time ago and cannot really remember all that much - except that they were impressive. Same counts for Harry Potter and The Lord Of The Rings - though that is just a whole different category for me. Those books will continue living for me, for the rest of my life.

Were you expecting The Hunger Games as a Best-book of Worst-book?
And I think there's a huge difference between best books and favourite books. Some books are incredibly well written, others are simply very very enjoyable and exciting, like The Hunger Games, while the style of writing may not be very extraordinary... (However, you could of course reason that being able to write very enjoyable and exciting books is quite extraordinary). So it's always a dilemma for me which books to mention

I think THE HUNGER GAMES was great. One could argue that Suzanne Collins' writing is amazing too. Although it is not exceptionnal and very literary etc., she has this amazing writing style that sucks you in, and how many authors can accomplish that?

To go back on-topic:

My absolute worst book, ever?
THE SELECTION by Kiera Cass. It is a YA dystopian, The Hunger Games meets The Bachelor. Great premise, poor execution. There is no distinguishable plot, the heroine is even worse than Bella, no swoon-worthy love interests, weak world building and I could go on for a long while. The worst thing was that this story could have been great. (On top of that, there was a lot of drama surrounding this book, with the author's agent publicly bashing a reviewer.)
The worst fantasy books? Terry Brooks is definitely a front-runner. There was no originality involved, and I'm tired of the LOTR rip-offs. Christopher Paolini's BRISINGR was quite horrible as well.

So, the best fantasy books? Harry Potter, but that is obvious. I enjoy Robin Hobb books as well, but her Liveship Traders Trilogy will always hold a special place in my heart. I fell in love with her world and her characters and I really hope she'll continue to write books set in the Realm of the Elderlings.

It's not that

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Finnick died (which was heartbreaking)

and that the other characters did not have time at that moment to ponder over it. However, I thought

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the grief would hit them at the next quiet moment, but it didn't.

. On top of that, I was very disappointed

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Katniss fell apart at the end, I kept wishing she eventually get it together.

THG definitely was a good series though. The biggest disappointment is that it caused some kind of trend, where (not even a good) romance is poorly disguised as a dystopian. (But then again, other dystopians such as DIVERGENT and LEGEND are awesome, so everything has its positive and negative sides?)

Worst part? THE SELECTION is a bestseller. Just not that epic.

I think certain events were right, but Katniss

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had been so strong throughout. I can see her grieve and I can see her need to take her time, but in the end she had to be OK. Not the same as before, but OK.
Besides that, Katniss only had kids because Peeta nagged her about it. Uhm... That does not really correspond with the Katniss from THG and Catching Fire. What happened to Prim does not help the case either.
But I guess what really disappointed me was that Katniss did not solve the love triangle herself. While I agree with the outcome, she should have been the one to make the final decision. The author makes it too easy by making Gale feel like he has failed in his one purpose, aka protecting Katniss and her family, and thus has to leave, while Peeta just presents himself to her.

Overall, I thought the final book was the weakest of them all, but still very enjoyable.

Same for me! While I felt some things in the last book were rushed too much, I liked the irony...

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I mean, it all started out because Katniss wanted to protect her sister from the world, and then, in the end, it turned out she couldn't, which indeed makes it realistic that Katniss would be devastated. I found it quite fitting, and I liked the fact that it was a rather sad ending. (Normally I'm all for happy endings, but in a world like this, that just didn't seem possible. Some people had to suffer).
But the not solving the love triangle-thing annoyed me too! I was continually thinking: 'Make the choice already!' (I have to admit I was all for Peeta, since I actually kind of hate love triangles. Besides, I always saw Gale as just a friend, so the whole romantic thing-that-could-have-been with him took me by surprise. I'm just oblivious )