Is it ok for me to wear a sari to my prom?

Yeah, it's beautiful! And you shouldn't be ashamed of your cultures clothes, you won't look like an outcast, just wear the Sari... it's so nice. It would look better than any western dresses, for sure. And as for guys, it depends what they're into I guess. Some guys will find it gorgeous, others may find it unusual. Who cares though?