-shu is also "酒" that means alcoholic beverage.
Daiginjyo and Ginjyo I posted about with Seimaibuai (rice polishing ratio) on the previous post, so I'll skip for now.
Jyunmai is made from only rice, malted rice, water. None distilled alcohol.
Futsu (普通) means common, ordinary, usual, general, normal, average, medium etc.
Here is a simple chart to know about SAKE (Nihon-shu 日本酒)
If you have interest, you can but it direct from Japan on Rakuten Global so enjoy!
Note: Some countries are restricted to import alcoholic beverage. Check before ordering SAKE.