You'll probably find more variety in Asian groceries in the Strip district. But Tokyo Japanese food store supplies things that even Bai He (lotus) doesn't and is closer to the universities.
There's an aisle dedicated to ramen. There's a shelf dedicated to cute drinks like ramune, green tea, calpico, and pocari sweat. There's also a shelf with bowls and cups which might make a nice present if thats what you go for.
They have fresh shiso leaf, frozen sushi fish, and specialty vegetables that you would find in Japanese cuisine such as lotus root. They also have half a cooler section with different types of miso. I like to get a red miso and a white miso. You can get actual asian tofu instead of the american (very firm) kind. By the cashier, you can get buns and breads from an Asian bakery. It's not particularly fresh, but if you're missing the taste you might want to try it.
I'm pretty sure there's a ramp for a wheel chair. The aisles though are pretty narrow so be careful.