Hi Nats,
I used to live in Weybridge, so saw a few when I was looking at nurseries for DD.
My DD ended up going to Tadpoles, which used to be in Walton, but now has relocated to Herhsam. It was reasonably priced and I thought that the lady who runs it was absolutely wonderful - all the kids loved her. You could tell from the pricing, but it wasn't the flashiest of nurseries, with the best of facilities. I'm not sure how good it is for older children, but as I said, they've moved to a much bigger facility now, so I couldn't comment on that.
Another nursery I really liked was Martyr's Green in Cobham. With these things, I find that you check your list of things e.g. security, hygiene, food etc., then make a decision based on your gut feel. Martyr's Green is expensive, but the (damn inconvenient) location is lovely, lots of light and space, and I warmed to the staff. However, it is one of those places where you pay through the nose. I put DD on the wait list for Martyr's Green, but we moved before a place became available.
Other friends have their children in Liliput's in Hersham, and speak very highly of it.
We've moved a few times, so I'm au fait with nurseries nowadays! I find that the more places you go to, the more you trust your instinct. Good luck!