I've been in this type of situation before over the years. You want to say something but don't want to make her think you're some kind of creep or weirdo. I usually break the ice by saying something like With hair that pretty, you could be making commercials for pantene lilke I see on TV. Than don't say anything else. The ball is in her court. See how she responds. It's innocent enough that she won;t be offended, it's a compliment without being too forward and I have never had a woman take offense to it. If it doesn't lead anywhere, then no harm done. But often it will lead into a pleasant conversation and then some.

Good luck.