This was me last Spring. In then end I bought 2 pairs of the stretchy ones (the ones that bend up when not being worn), and they're perfect. I was finding I was having to do toe claw to keep other ballets on.
I've got one pair from Jones, but they're very, very flat with little support, so I like them, but wouldn't wear them if planning on doing much walking. I also have 2 pairs now of the Abbey ballets from Banana Republic (second pair bought in the sale), and they're great - cushioned sole, stay on my feet, comfy.