Actaually Tagalog and Japanese tie for second in the "foreign" language category. Pidgen is English with a Hawaiian twist. I am def. not an expert in Pidgen, but you hear things like this....
Depends what you're trying to do. If you want to get a job in the tourism industry, it's still Japanese. Other prominent languages are Tagalog, Ilokano, Chinese (Mandarin & Cantonese), Korean. Theres immigrants from all over the world here.
I'm not sure what I want to do exactly. I'd like to move to Hawaii one day and I like studying languages, so I thought I'd concentrate on what would be the most useful there. Japanese is probably a good way to go for me since it would be useful there and I already have some study materials for it. I've never tried Tagalog though. I may have to look in to that one.
Without a doubt, it's Japanese, since tourism is one of our biggest three industries, and most of the tourists hail from the land of the rising sun. There are a lot of Cantonese speakers too. I don't think that Tagalog would actually be that useful, since most of those people can also speak some degree of english. Most of the Japanese tourists dont speak much at all, and the older Chinese population don't speak much english either.