Toyota Repair: 95 Corolla died on freeway, distributor shaft, seizer

Question
Two days ago, my wife was making her 60 mile drive home in our 1995 Corolla (1.6L, 162K miles, Automatic, did run great). 15 miles from home, driving about 70mph, she suddenly heard a faint clicking from the engine compartment, with no warning lights, temp normal, no unusual smells, A/C off, for about 30 seconds. The car gradually lost power during those 30 seconds, then died completely...followed by what she described as "the sound an electric fan makes when you turn it off and it's slowing down". After stopping, she immediately attempted to restart. Upon doing so, there appeared to be no power at all. 5 minutes later, trying to start the car (power back) resulted in a single "clunk" sound, as if something was holding the crankshaft in place. When I now attempt to start the car, I get the same thing, though it almost sounds like "clunk", "ping" (The starter definitely sounds like it's engaging). The engine just won't turn. I checked the battery...it's fine. Checked the drive belt components (Alt, Water Pump, Steering pump) for seizer. But have not checked the A/C clutch, nor attempted turning the motor by hand. I pulled the plugs, and they looked excellent. I then ran the self-diagnostics resulting in Code 12. I then pulled the Dist cap and visually noticed that it appeared the rotor made slight contact with the cap wall...enough to create a shiny surface on half the outside rotor contact, with some scratching on the inside of the rotor cap. The way the scratching looks, it appears abrupt, not from continued rotation. I checked the primary and secondary resistance and it checked out fine. The distributor shaft appears straight and solid. Another fact is that the lights (interior) dim almost off when attempting to crank the motor. Is it possible for the starter to have engaged while driving? Something in the valve train (or below) broken? I keep leaning towards a mechanical issue...something seized or broken. I replaced the starter about a year ago obtained from Advance Auto Parts (which makes me suspicious). Any thoughts/suggestions?

Answer
Remove the starter and see if the engine will turn over by turning the crankshaft pulley, as you suggested it is very possible that the starter engaged and seized and so, not letting the engine rotate, do this first and let me know if I can be of more help.