Does this cavity have any hope of remineralizing?

I had my teeth cleaned and x-rays taken this morning and the dentist mentioned that I may have a cavity on the blurry spot on the x-ray. I'm not sure I want to have the tooth filled because I'll have to lose some amount of perfectly healthy tooth to get there. The dentist gave me a high fluoride/remineralizing paste (prescription) which I will use in the meantime. I wanted to ask though, does this seem like something I should get filled right away? Should I seek out maybe some ozone therapy or something to try to stop the bacteria?

X-ray image: http://i.imgur.com/fmEUCGi.jpg

(Sorry, I could not get the Upload Image button to work)