I hope I can provide my own personal experience...
The only time I have heard about breaking in tires is with motorcycles. That is because new tires come with a coating on them that could make it slick if you push the tire a lot on a ride. I would imagine the same would be for a car tire.
As for the rolling resistance thing... Yes as tires age the rolling resistance does decrease. Here is an article about that...
Tire Tech Information - Tire Rolling Resistance Part 3: Changes to Expect When Switching from Worn-Out to New Tires
The dry rot tiger paw tires were dangerous. The best thing you could have done for your own safety and the safety of others around you was to get some fresh rubber.
as for tire choice? Here is a thread
http://ecomodder.com/forum/showthrea...res-12918.html