I got the impression that OP is looking for a small intimate place with quality food, not looking for a restaurant which can handle seating for 50 people at once. My impression of mom and pop type place is small, nothing fancy, and food is average at best. I am getting the impression that OP is not looking for a place like this. Also, if OP wants to go to true mom and pop type place in Japan then do need to read and speak Japanese.
This is first trip to Japan for OP. Last minute trip, rushing to plan detail. Then if OP does not read or speak Japanese, then I recommend that OP to stick with places catering to foreigners (non-Japanese) such as Ritz. Same for choice of restaurants. You really do not have time to study each different place. If you try too creative and look for places little off the beaten track, then it is good chance you will end up with places not to your taste.