Hm, I'm not sure how Flash works in this instance, but my initial reaction to any mention of using it in web pages is that it's had its day, and is better not used—unless perhaps for video.
How has this actually been set up on your site? Are you using a CMS? Most of them will have ways to add images to a gallery that uses pure HTML and CSS (and perhaps some JS for nice enhancements).
There are also 3rd party photo gallery add-ons that are quite good. For example, Slideshow Pro Director is very nice. You also have a nice guarantee that the gallery will work on devices that don't support flash, such as Apple's i-devices.