Which language should I learn?

So, for my 15th birthday, my aunt is buying me a language software in whatever language I want:D problem is, which language? I've taken French for years, and absolutely hated it. My dad has Spanish software, so I was going to use his when I go visit. I'm a HUGE anime/manga fan, and would love to take Japanese, except that I don't think I would get any use of it:/ I am also interested in German, since that is what my family is. But, should I instead take a language that would be useful? I don't know. So, would Japanese or German be more useful/fun? I'd be happy to learn either! Or, should I take a different one? Just not French!