Either... or both 
I would go with the 18-55mm all day long though, the 18-55mm is fantastic, and I don't typically like zooms. It's silent, well built, light, has great OIS and it's a solid performer.
I also resent the comment of the 18mm f2 being "not that great", it's tied with my 35/1.4 for favorite lens 
As for the weather sealing comment... maybe I've just been very lucky for as long as I've been shooting, but the only weather sealed camera I've ever owned prior to my X-Pro2 was my 6D and with that camera I didn't even have any weather sealed lenses for very long (sold my 24-105L shortly after buying the kit) and I take my cameras all over and shoot with them in any weather I happen to encounter and so far haven't had any issues.
My Fuji kits have been in snow, light rain, at the beach, in and out of very hot humid summer days and cold AC interiors and while the condensation is annoying when you forget to take the proper preventative measures, it hasn't ruined anything.