That depends on what the houses are worth versus what you'd be paying for them. It also depends on the rental income that could be generated from each.
From a rental standpoint, assuming the two are both fairly priced and that the income from each covers the same percentage of mortgage, I'd go with the older home.
If you're planning on living there, then it's not an investment. In that case, weigh the factors that are important to you. Just one thing to keep in mind--and I'm saying this as a parent of a child who recently was in the public school system: The individual school counts for a lot. My son went to a supposedly excellent elementary school in what is generally considered a very good quality school district. It was a horrible experience. After elementary school, he went to a secondary school in the same school district. The secondary school has a good reputation, but not the sparkling, outstanding reputation of the elementary school. From my son's perspective (and from ours), that school was absolutely terrific. So while you certainly should consider the school district (using whatever parameters you consider important), do NOT let that be your sole criterion.
As for specific properties, room layout, traffic flow, usable area are all important. And let me tell you a little secret: In 10 years, granite countertops and stainless steel appliances will date a house just as surely as avacado appliances or butcher block laminate do.
And while you may be concerned about old versus new construction, you probably have it backwards: Old construction likely is a heck of a lot better than most of what's being put up today.
Finally, you ask about "the long run." Today, one house is new and one is 30 years old. In the long run--say 20 years from now, one house will be 20 years old and one will be 50. That new house won't be new any longer.
So, as an investment, run the numbers. That's all that counts.
As a home to live in, consider the house. Consider the neighborhood. Consider proximity to shopping, jobs, etc.
Hope that helps.