Definitely offer up a copy of The Napoleon of Notting Hill. It’s an early science fiction novel by G. K. Chesterton, one of the greatest English authors of all time, with lots of whizz-bang action and a terrific ending. Perfect for anyone who likes “Victorian SF” or simply a generally quaint feel to their novels. Plus, if he decides that he likes Chesterton, there are almost a hundred equally good books to turn to next.
I was going to suggest this very one (in fact these are the only two Moore books I’ve read… yet - have a copy of Coyote Blue at my side as I type). Yeah, one of the main characters dies in the end, but your friend knows that already so it’s not like it’s a surprise! (and of course, well, he only stays dead for what, a couplea days? ;)).
It is the only winner in the novel category that is a comedy. None of the books that have won the Nebula are intentional comedies either. 
Willis has won more Hugo awards than any other writer with her total currently standing at ten. She’s outpaced only by a handful of artists and editors who have managed to mode-lock the Hugo voters so they were handed the award by rote year after. Willis is also the only person to win in the novel category and a short fiction category in the same year with Doomsday Book and “Even the Queen” in 1993; only two other writers have managed to win two Hugos in a single year. Both of those managed to win the Nebula that year as well.