What is the best commuter bike tire? My fiancee expressed interest in going on rides together, so I borrowed my mom's old purple Univega Via De Oro that's running 21sp Shimano STX-RC.  I replaced the cables and overhauled the shifters, and rides had been going well.  Yesterday I pulled the bike off the wall to find that the front tire was flat.  The tires are TopGear Stratos 700x35c on Mavic 622x17 rims, and they're feeling kinda brittle.

Edit:
Which compounds make up a tire or what should I look for in a tire to meet the following qualifications:
Thorn resistance
Comfortable ride
Enough width to reduce getting trapped in ruts
I don't care too much about rolling resistance.  We're going on fun rides.  I just don't want to worry about changing the tube frequently.
Thanks in advance!
Whenever you are not aiming for riding in a race, go for serious puncture proof tires. Especially if you are a casual rider who can't just fix a flat within 10min on the road side. I certainly can't, even though I've patched enough tires for a lifetime. You are not going to get significant enjoyment out of being able to ride 0.1km/h faster, but you are going to get significant enjoyment out of not having to stop and patch every 100km, or so.