Okay. Running store.
I've had good and not-as-good experiences (good when I went for me, not-as-good when we went for my sister). The key is to make sure you feel comfortable. If you feel like anything is making you uncomfortable, then tell them you're not going to buy the shoes and walk out.
If you're nervous, talk it out with the salesperson. The good thing about going to a running store is that most likely the person you're dealing with is also a runner. They may remember their first time getting fitted for shoes. If you're lucky, you may even get another Disney runner who really understands you. And if you're looking for a local half before Wine & Dine ... talk to the people at the running store and see if they have recommendations.
You can also tell them that you've had success in the NB Disney shoes before and you'd like to try the a version of those (I don't remember which ones you have, but they should say the model number on them somewhere, and the running store may have the latest version of that model). I went in and told my running store that I've done well in Asics and wanted to try some Asics, and they gave me two different types of Asics to try (and I ended up walking out with New Balance shoes...). If you go to the right store, they will want to make the experience painless for you.
Remember that the running store is interested in making you happy (after all, if you like going there, then they just got someone new who will buy things and spend money). If they don't seem interested in making sure you're happy with your purchase, then you're in the wrong store.
(And by the way ... I don't consider myself a serious runner either. I'm a consistent runner, but not at all serious about it. I still go to the running store all the time. Nobody says it's the "serious runners only running store." A good running store will cater to all runners at all points in their journey.)