Yes, any peppermint tea should work. It all really depends on your taste. I went through about 4 tea brands before I found something I liked. Even then, I prefer to make it fresh (boil some from the garden).
Yes, ginger root can usually be found at the grocery store. I found the Asian markets usually have it. It would be best to make a tea out of it - boil a chunk in a pan with water. Again, it's about taste, trial and error. Play around with the size of root and how long you boil it with how much flavor you like.
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