Well, let me tell you about my experience with the Japanese. They are kinda obsessed with Americans. (I don't really know why...) But for the most part, if you're an American, they will get really excited (or shy).
Anyways, they are very hospitable, respectful, and kind. They will always be willing to help if they can. They will want to try to speak English with you to get better, which makes sense because it is mandatory for them to learn the language, but they don't have much real-life experience.
Now, yes. There may be some prejudice. There is everywhere you go in the world. Everybody has a problem with somebody. I find that it is mostly the older generation that has a problem with foreigners (i.e. Americans.) To be frank, it is hostility left over from WWII. Who can blame them for feeling upset. If you look at America, "white" people tend to be somewhat prejudice to Japanese because of Pearl Harbor. But this is all completly stupid. After all, it wasn't the people who really did that, it was the governments who made the decisions. The people were the ones who sufferred. It also depends on a person's background, like how they were raised. For example, I was raised in a wholesome family and I am not a prejudice person. My grandfather was tortured by the Japanese, but I still love the country and its people with all my heart. I am NOT going to just blame any Japanese person I see for what happened to my grandfather. However, not all people think like that.
Well, back from that rabbit-trail.... (^_^) When I went to a Japanese elementary school (note: I look 1/2 Japanese and speak, read, and write it....so I'm not the typical "foreigner") the kids gathered around me and we did oragami together. They brought me food and played their recorders and sang for me. Later, when I was leaving them, the kids of the family I was with wouldn't stop crying. I can remember the woman cry, too.
The tenderness and love I felt from Japan could be a reflection from the love I have for it. I suppose the moral of this is, if you show a true effort and have a great liking for their country, it will be evident without words and people will react, sometimes without realizing.
I was terrified as well from the rumors I had heard, but you really have to go and find the truth for yourself. I could go on and on...(but it would be too long
Anyways, good luck in Japan!!! Ganbatte ne!