My favourite story is the one where Thor gets dressed up as a woman for Freya's wedding. I also like the one where Frey first sees his wife. My nine-year-old kid likes the one where Thor goes fishing and catches the world serpent the best.
My favourite hero, who I always include in sumbel, since he's a real historic person, is Jarl Haakon.
My favourite creepy creature is Fafnir, that Sigurd slayed in th story of the ring, but there are sooooooo many good ghost stories in the Norse mythology!
My favourite book is Heimskringla, but really, one should start with the Havamal (part of the Edda).
As for what happens after Ragnarök, you will get many answers depending on who you ask. Some believe that the whole concept of there being anything at all after Ragnarök was something thought up as an influence of the Christian faith upon the Norse, while some do not. In other words, it really has to do with what you base your faith upon - historical pretence, intuition, and if historical pretence, which part (era) of history, as the faith has not stayed unchanged. To a large extent, the sagas were written down by one or more Christian monks several hundred years after Christianity had taken over, and so each one of them would have understood, interpreted and copied the story down differently according to their own cultural context. Even the creation myth differs depending on which version of what saga you read....
I was born right the first time, no need to be born again.