Mouse-Over display of another HTML in layer

Given that I know how to cause a mouse_over or mouse-click display of a
larger version of an image just below and to the right, or some other
visible position given screen size of the user, of the one originally shown.

http://www.wgtn.net\Community\Housing\apartments.htm

I would like to be able to display a panel of photos that is in HTML code,
rather than just an image.

The use is for a Class Reunion page where I plan to dicplay a classmates
photos from Seventh grade through Senior year side by side when they click
on their name or photo. This panel of photos is in HTML code.

Since I do already use Iframe to do this in selected cases where the display
is in a fixed permanent position in the document, I do know it is possible
to display one HTML document within another and to let the user make a
dceision which of several HTML documents ot display there for their viewing
convenience.

What I am seeking is to be able to diplay an HTML photo panel, rather than
just an image and for it to be next to the original image, rather than a
fixed permanent place on the document physically removed from where the
mouse-over takes splace. This is something like that Iframe idea, but
floating rather than fixed and next to the original image that caused the
user to do the mouse-over or mouse-click rather than remotly somewhere else
on the document.

Does anyone have an example they can point me to for this?