do i have to pay the immigrant vis fee $350 to the embassy or will i just pay the $100 for the nonimmigrant visa fee

You just have to pay the $100 @ any paymaster and bring the reciept to the interview.

I see that you have your interview at the beginning of April Good Luck!!!

It is just the $100.00. I was so worried when I went down for the interview that I did the I-864 for the immigrant visa too (and had the $375.00 cash)......just in case.