The 15 must mean internal width, and if so you should be able to run any traditional road tire. At your weight a 23mm at 100psi front and 110 rear is pretty standard, or go with a 25mm at a little less pressure if you like a smoother ride.

For tires, I don't know what your budget it, but Michelin Pro 4 Endurance are a good durable tire that still has a decent ride. I'd start there.