Where are you finding the leaks in your tubes? If you're getting pinch flats, that's probably from riding over curbs and such, in which case running too much pressure isn't your problem. Are you getting punctures from road debris? In that case, you might want a tire with some puncture protection features, such as Continental Gatorskins or Schwalbe Marathons (though those specific tires may not be appropriate for your bike for other reasons). Are you getting leaks around the valve stem? If so, a different tire probably won't help, and your riding style isn't to blame, but you need to look at how you're mounting tubes and inflating them.