Thanks for all the info and replies. I sincerely appreciate the guidance . FWIW, I contacted Schwalbe and Continental. The former was quick to respond with a recommendation and the latter still has not replied.
The rear tire is worn , so I will probably rotate it and let him ride for a while and burn through it a bit. Based on what you people said and what Schwalbe offered, I ordered the Marathon GT 365. They are probably more tire than he needs, but sound like they will be road worthy and not frustrate him/us with flats. So far he has been flat free on the stock, cheapo , OE tires. I would like to keep it that way.
Below is the reply I received from Schwalbe:
Thanks for the message. Judging by everything you said I think the perfect tire for your son’s bike would be our
Marathon GT 365. It’s a 4 seasons tire designed to very high levels of puncture protection and maximum grip on pavement even when it’s slippery out (winter riding would even be possible, the only limitation would be where there is a lot of ice and then only studded tires work). Basically they are a very tough road/city/commuting tire that you can do ANYTHING on, but offer the absolute maximum amount of safety and confidence that we offer in a tire.
The part number is 11101343 and they run $51 each.
The tire size is called 28x2.00’’ but don’t be confused, this is the correct fit to replace a 29x2.25’’ MTB tire (the replacement will fit perfectly on the rim, but will inflate to 2’’ wide instead of 2.25’’ wide, which will actually improve the bikes performance on the road).
This is a non-folding tire (wire bead) as per your preference.