I also have the same size as LenA, 26x1.85, and I have run 700x40mm. The 40mm was actually a bit wide on a 700c rim, as the rotational inertia was a bit higher than desired. The 1.85" size, while being 50mm wide, has less rotational inertia thanks to the smaller, faster rim (559 mm instead of 622 mm). I've had one flat in about 5000 miles, and it was on a pyramid shaped piece of glass that would have punctured anything short of a solid rubber tire.
Rolling resistance is pretty good, though I definitely do NOT recommend running them at max inflation as lenA describes, as they are MUCH MUCH slower at that pressure. I weigh about 205# and find 50-55 PSI front and 55-60 PSI rear to be optimal on smooth roads, and 35-40 PSI front and 40-45 PSI rear on rougher roads. Running them at 87 PSI (the max) feels faster, since it's a rougher ride and rougher gives the sensation of going faster, but my bike computer shows around 2-3 MPH loss in speed when running them at too high of a pressure.
My 26x1.85 tires have a few nicks and scrapes on them and the one puncture hole, and the tread is getting a bit thinner than I'm comfortable with after about 4,000 miles so they'll be replaced soon. I'll be replacing them with Continental Contact Winter II tires until probably late March, then either getting a new set of the Michelin tires, or possibly something else, I haven't decided yet, but the Michelin City tires are definitely a very good tire for the money.