4 hours alone together! Yikes! I can understand your trepidation! Ask him:
*What he wanted to be when he grew up *His favorite childhood memory *His favorite teacher in school *The first girl he had a crush on *His favorite type of food *His favorite animal *His least favorite reptile *If he had $50,000 to spend on a friend's party, what would he spend it on (my WH said he would never spend $50K on friend, only himself - BIG surprise, lol!)
--Out of the blue stuff like that. It's fun, it's unexpected, and you can learn a lot. Warning: mood counts. If he's in a playful mood, it will be fun. If he's in a bad mood, save it until he's in a playful mood.
Have fun, learn lots, and let us know how it goes!