Use "interested in ___ing" to talk about things that you want to do, when you're discussing them in a general way. "Want" has an immediate feeling. You use it for something that you want to do soon:

I want to go to Disney Land!

But you use "interested in ___ing" for things that you think would be fun, but you're not planning on doing them really soon and you might not do them. This is good for asking people questions about something you might do in the future:

Are you interested in learning French? I'm thinking of taking a class, but I don't think I'd really be able to stick with it unless I had a friend taking it with me.