As far as art goes, and life in general for that matter, I will try anything once.
Right now I work in advertising part-time. It's not nearly as cool as it sounds, I am really just a sign monkey. I pretty much create all the signs, banners, promotional stuff. (All using graphic design programs, digital camera, design software, etc.)
As far as hobbies go, I write short stories, poems, wrote one play (sucked), paint (oil and watercolor), draw, (ink, carcoal, pencil, pastel), quilted a few times (stuff turned out really really cool but I didn't have the time to do more), I cook like a mo fo, (that's a good thing), and used to do some photography, but my cool camera got stolen and I haven't replaced it yet, I just have a crappy little thing now. Future Horizions--who knows...I'll probably putter with stuff all my life, nothing serious tho.
I also used to be in all sorts of plays, and stuff in high school. Last semester I was in a performance group, it was pretty fun. I am pondering doing it again this year. It's called Players, and they do a theme, write their own pieces, and then perform them as a group. It's cool, but the next theme they are doing is Religion--I might be too emotional to participate.
As far as art therepy goes I think it's a great idea for ANYONE. Doing performance stuff like Players really illustrated that to me. At first I was totally against it, "it's not real acting", "what a bunch of freaky hippies, art farty freaks." etc. But you really do dig deep, and find some stuff out about yourself you didn't even know existed. But I also thing other types of art therepy are just as relevant and helpful.
As far as themes go: Family, Obedience, Love, God, Disapointment, Loss...you name it, it could be used as a theme.
As for the the last question...about performance, I'm not sure I get it...s'plain more please