Just about any tire is going to be vulnerable to punctures especially as they age/wear. I've found the Continental GatorskinContinental Gatorskin tires to be effective and I match them with Mr. Tuffy tire inserts. As long as I check the tires for embedded thorns/glass every few weeks, I can go a few thousand road miles or more without a flat.
The downside of using inserts and thicker tires is the weight increase. To me, this is negligible and well worth the decrease in flats.
