If you need to fade a set of images in and out of each other, all in the same box, this jQuery slide show animation plugin might do the trick for you:

http://www.gruppo4.com/~tobia/cross-slide.shtml

This can give you some of the nice fades and transitions that used to be found mostly in Flash-based solutions. The example there are nice, but you also can have a lot of control over how the animations look (think Ken Burns effect, with panning, zooming and fading all going on at once).

I fired this thing up in IE6 to see if it would pass muster and the examples worked. Kudo's to the author (Tobia Conforto) for that. This is a nice plugin to remember when you want to put in some nice self-contained image gallery animations.

If you're in the market for something for this, you might also want to take a look at the jQuery Cycle Plugin, which I've noticed is well supported in the jquery Google group (and I've used it for a few things, with success).